General Information
Symbol
Dmel\per
Species
D. melanogaster
Name
period
Annotation Symbol
CG2647
Feature Type
FlyBase ID
FBgn0003068
Gene Model Status
Stock Availability
Gene Snapshot
In progress.Contributions welcome.
Also Known As
period, dper, Clk, EG:155E2 .4
Genomic Location
Cytogenetic map
Sequence location
X:2,685,580..2,692,780 [+]
Recombination map
1-1.5
Sequence
Other Genome Views
The following external sites may use different assemblies or annotations than FlyBase.
GO Summary Ribbons
Families, Domains and Molecular Function
Gene Group Membership (FlyBase)
Protein Family (UniProt, Sequence Similarities)
-
Summaries
UniProt Contributed Function Data
Essential for biological clock functions. Determines the period length of circadian and ultradian rhythms; an increase in PER dosage leads to shortened circadian rhythms and a decrease leads to lengthened circadian rhythms. Essential for the circadian rhythmicity of locomotor activity, eclosion behavior, and for the rhythmic component of the male courtship song that originates in the thoracic nervous system. The biological cycle depends on the rhythmic formation and nuclear localization of the TIM-PER complex. Light induces the degradation of TIM, which promotes elimination of PER. Nuclear activity of the heterodimer coordinatively regulates PER and TIM transcription through a negative feedback loop. Behaves as a negative element in circadian transcriptional loop. Does not appear to bind DNA, suggesting indirect transcriptional inhibition. Required for binding of cwo to the E box regions in the promoters of target genes of the transcriptional activator Clock, probably by binding to Clock-cycle heterodimers, reducing their affinity for E box binding and allowing cwo to bind instead (PubMed:27814361).
(UniProt, P07663)
Phenotypic Description from the Red Book (Lindsley and Zimm 1992)
per: period (J.C. Hall; M. Young)
The per gene is essential for biological clock functions and determines the period length of circadian and ultradian rhythms. The per mutants are characterized by aberrant rhythms involving eclosion and locomotor activity (Konopka and Benzer, 1971) and may change the rhythmic component of the male courtship song (Crossley, 1988; Ewing, 1988; Kyriacou and Hall, 1980, 1986, 1988). These mutants also affect the rhythm of the larval heartbeat (Dowse, Ringo, and Kyriacou; Livingstone, 1981, Neurosci. Abstr. 7: 351), the level of tyrosine decarboxylase [Livingstone and Tempel, 1983, Nature (London) 303: 67-70], and fluctuations in membrane potentials in larval salivary glands (Weitzel and Rensing, 1981, J. Comp. Physiol. 143: 229-35), modulate intercellular junctional communication (Bargiello et al., 1987), and alter the location of neural secretory cells in the brain (Konopka and Wells, 1980, J. Neurobiol. 11: 411-15). In wild-type flies the period length is about 24 hr. In general, increases in per+ dosage lead to shortened circadian rhythms and decreases lead to lengthened circadian rhythms (Baylies et al., 1987; Cote and Brody, 1986; Hamblen et al., 1986; Smith and Konopka, 1981, 1982; Young et al., 1985). Females heterozygous for per+ and a deletion of the locus or a per0 allele show longer-than-normal periods. per flies can be classified on the basis of their circadian rhythms as: (1) Cryptic period mutants (per0, per-) which have a 10-15 hr (ultradian) period and appear arrhythmic except in special algorhythmic tests (Dowse et al., 1987); (2) Long period mutants (perL), 29 hr; (3) Long-period variable mutants (perLvar), which in homozygotes or heterozygotes are arrhythmic but in combination with certain partial deletions of the per locus result in a 30-34 hr period. (Konopka, 1987); (4) Short period mutants (pers), 19 hr; (5) Short period variable mutants (persvar), some flies having a 20 hr period and the others a normal 24 hr period for locomotor activity. In temperature-change experiments on pers and perL1, the locomotor activity periods were found to be nearer to 24 hr at low temperatures, but to diverge further from normal upon heating (Konopka, Pittendrigh, and Orr; Hamblen, Ewer, and Hall). perL2 shows lengthening of the periods at high temperatures. The mutant types affecting circadian rhythms (per0, perL, and pers) may cause similar kinds of changes in the rhythmic fluctuations in courtship song interpulse intervals (IPIs) of the male (Crossley, 1988; Ewing, 1988; Kyriacou and Hall, 1980, 1986, 1988). per0 mutants show nonrhythmic variations in the interval between pulses of wing vibration. Neural studies show that transplantation of pers brains into per01 adult hosts causes some of the hosts to be "rescued"; i.e. to show short-period circadian rhythms for locomotor activity (Handler and Konopka, 1979). Octopamine synthesis occurs at subnormal rates in per01 brains, with a corresponding decrease in the enzyme tyrosine decarboxylase (Livingstone and Tempel, 1983); less severe decrements in tyrosine decarboxylase are found in pers and perL1 flies. Physiological studies show that per mutations can affect the level of gap junctional communication among cells in a tissue (Bargiello et al., 1987). In salivary glands the per0 and perL1 mutations cause a lowering of the level of junctional communication, while pers gives a level of communication higher than wild type. Because electrical synapses are composed of gap junctions, per may influence circadian behavioral rhythms through altered conductances at the synapse (Bargiello et al., 1987). Mosaic analysis of pers mutants indicates that the gene influences the brain with respect to aberrant locomotor rhythms (Konopka, Wells, and Lee, 1983, Mol. Gen. Genet. 190: 284-88); per01 and per02 (and, to a lesser degree, pers) are said to cause anomalous photonegative behavior in light-response tests (Palmer, Kendrick, and Hotchkiss, 1985, Ann. N.Y. Acad. Sci., pp 323-24), but in general are not defective in visual responses (phototaxis tests, optomotor behavior, and electroretinogram) according to Dushay and Hall.
Gene Model and Products
Number of Transcripts
2
Number of Unique Polypeptides
1

Please see the GBrowse view of Dmel\per or the JBrowse view of Dmel\per for information on other features

To submit a correction to a gene model please use the Contact FlyBase form

Protein Domains (via Pfam)
Isoform displayed:
Pfam protein domains
InterPro name
classification
start
end
Protein Domains (via SMART)
Isoform displayed:
SMART protein domains
InterPro name
classification
start
end
Comments on Gene Model
Gene model reviewed during 5.45
Sequence Ontology: Class of Gene
Transcript Data
Annotated Transcripts
Name
FlyBase ID
RefSeq ID
Length (nt)
Assoc. CDS (aa)
FBtr0070477
4527
1218
FBtr0332311
4441
1218
Additional Transcript Data and Comments
Reported size (kB)
Comments
External Data
Crossreferences
Polypeptide Data
Annotated Polypeptides
Name
FlyBase ID
Predicted MW (kDa)
Length (aa)
Theoretical pI
RefSeq ID
GenBank
FBpp0070455
127.4
1218
7.17
FBpp0304590
127.4
1218
7.17
Polypeptides with Identical Sequences

The group(s) of polypeptides indicated below share identical sequence to each other.

1218 aa isoforms: per-PA, per-PB
Additional Polypeptide Data and Comments
Reported size (kDa)
Comments
External Data
Subunit Structure (UniProtKB)
Forms a heterodimer with timeless (TIM); the complex then translocates into the nucleus. A proportion of the protein exists as homodimer.
(UniProt, P07663)
Post Translational Modification
Phosphorylated with a circadian rhythmicity, probably by the double-time protein (dbt). Phosphorylation could be implicated in the stability of per monomer and in the formation of heterodimer per-tim.
(UniProt, P07663)
Domain
Contains a remarkable run of alternating Gly-Thr residues which is polymorphic in length. At least three types of Gly-Thr length exist in the natural population, (Gly-Thr)23 (shown here), and two major variants (Gly-Thr)17 and (Gly-Thr)20. This Gly-Thr stretch is implicated in the maintenance of circadian period at different temperatures. Deletion of the repeat leads to a shortening of the courtship song cycle period, and thus could be important for determining features of species-specific mating behavior. Mutations in the PAS domain result in longer circadian rhythms and courtship song (PERL mutation) or makes the flies arrhythmic (PER01 mutation).
(UniProt, P07663)
Crossreferences
InterPro - A database of protein families, domains and functional sites
Linkouts
Sequences Consistent with the Gene Model
Nucleotide / Polypeptide Records
 
Mapped Features

Click to get a list of regulatory features (enhancers, TFBS, etc.) and gene disruptions (point mutations, indels, etc.) within or overlapping Dmel\per using the Feature Mapper tool.

External Data
Crossreferences
Eukaryotic Promoter Database - A collection of databases of experimentally validated promoters for selected model organisms.
Linkouts
Gene Ontology (39 terms)
Molecular Function (8 terms)
Terms Based on Experimental Evidence (4 terms)
CV Term
Evidence
References
inferred from physical interaction with UniProtKB:O77059
(assigned by UniProt )
inferred from physical interaction with FLYBASE:dco; FB:FBgn0002413
inferred from physical interaction with FLYBASE:tim; FB:FBgn0014396
inferred from physical interaction with FLYBASE:Clk; FB:FBgn0023076
Terms Based on Predictions or Assertions (6 terms)
CV Term
Evidence
References
non-traceable author statement
traceable author statement
inferred from biological aspect of ancestor with PANTHER:PTN000138364
(assigned by GO_Central )
inferred from biological aspect of ancestor with PANTHER:PTN000138364
(assigned by GO_Central )
inferred from biological aspect of ancestor with PANTHER:PTN000138364
(assigned by GO_Central )
Biological Process (28 terms)
Terms Based on Experimental Evidence (21 terms)
CV Term
Evidence
References
inferred from mutant phenotype
(assigned by CACAO )
inferred from mutant phenotype
inferred from mutant phenotype
inferred from mutant phenotype
inferred from mutant phenotype
inferred from mutant phenotype
inferred from mutant phenotype
inferred from mutant phenotype
Terms Based on Predictions or Assertions (13 terms)
CV Term
Evidence
References
non-traceable author statement
inferred from biological aspect of ancestor with PANTHER:PTN000138364
(assigned by GO_Central )
traceable author statement
non-traceable author statement
non-traceable author statement
inferred from biological aspect of ancestor with PANTHER:PTN000138364
(assigned by GO_Central )
non-traceable author statement
traceable author statement
traceable author statement
non-traceable author statement
inferred from biological aspect of ancestor with PANTHER:PTN000138364
(assigned by GO_Central )
inferred from biological aspect of ancestor with PANTHER:PTN000138364
(assigned by GO_Central )
traceable author statement
traceable author statement
Cellular Component (3 terms)
Terms Based on Experimental Evidence (3 terms)
CV Term
Evidence
References
Terms Based on Predictions or Assertions (2 terms)
CV Term
Evidence
References
inferred from biological aspect of ancestor with PANTHER:PTN000138364
(assigned by GO_Central )
traceable author statement
non-traceable author statement
non-traceable author statement
traceable author statement
inferred from biological aspect of ancestor with PANTHER:PTN000138364
(assigned by GO_Central )
Expression Data
Transcript Expression
expression microarray
Stage
Tissue/Position (including subcellular localization)
Reference
adult brain

Comment: per mRNA levels do not significantly differ between ZT4 and ZT16.

in situ
Stage
Tissue/Position (including subcellular localization)
Reference
northern blot
Stage
Tissue/Position (including subcellular localization)
Reference
RT-PCR
Stage
Tissue/Position (including subcellular localization)
Reference
Additional Descriptive Data
The levels of per transcript oscillate throughout the day in a circadian fashion, similarly to tim but in contrast to inc. Expression of per is highest between ZT10 to ZT20.
RT-PCR analysis indicates that the levels of the per transcript cycle when in light:dark conditions, in anti-phase with the levels of the Clk transcript. per transcript levels increase gradually from ZT02 to ZT14, and decrease after that until ZT20.
per is expressed in adult oenocytes and shows a sinusoidal expression pattern with a peak at night and a trough during the day.
per transcripts show circadian cycling with a pattern that is antiphase to that of Clk transcripts. Peak values of per transcripts occur in the early night.
per transcripts are expressed in photoreceptor cells in the eye. They are also expressed in a wide region between the optic lobe and the central brain which includes the lateral neurons. They are expressed in the same pattern as dco transcripts.
per transcript levels in adult flies are not affected by exposure to light.
There is a dramatic rise in transcript level between Zeitgeber time (ZT)6 and 10. The level remains high for 8 hours, then drops precipitously by ZT22, suggesting that per mRNA cycling is transcriptionally regulated and that per mRNAs have short half-lives.
Marker for
 
Subcellular Localization
CV Term
Polypeptide Expression
No Assay Recorded
Stage
Tissue/Position (including subcellular localization)
Reference
immunolocalization
Stage
Tissue/Position (including subcellular localization)
Reference
CNS glial cell | subset

Comment: At the border between adjacent neuropils

DN1a neuron

Comment: DNa are found 15-30um anterior of DN1.

western blot
Stage
Tissue/Position (including subcellular localization)
Reference
Additional Descriptive Data
The levels of per protein oscillate throughout the day in a circadian fashion, in contrast to inc. Expression of per is highest between ZT0 to ZT4 and ZT16 to ZT20.
per protein starts being expressed in the embryonic brain at stage 12, extending gradually to 130 neurons at stage 16; a hundred of those also express Scer\GAL4per.PK. per-positive neurons are found throughout the brain but with more cells located caudally. Around 20 cells co-express per and tim. These cells are located in the lateral protocerebrum, close to where the lateral and dorsomedial larval clock neurons are found. Expression of per in the ventral nerve cord starts at stage 12 in 2-3 neurons per segment close to the midline. The number of labeled cells increases until stage 16, when per is detected in 8 midline cells and 11 pairs of lateral cells per segment. Co-expression with en is found in 3 VUM interneurons and one UMI interneuron, four other midline neurons and two lateral cells per hemisegment.
per is detected in follicle cells from oogenesis stage S2 and is not detected in stage 10 or later egg chambers. It is not expressed in every cell, resulting in a patchy expression pattern.
per protein shows robust circadian cycling in the pacemaker neuron of wildtype flies.
At 1 hour before lights on in an LD cycle, per is predominantly nuclear localized, close to the nuclear membrane. per protein levels are highest 3hrs before lights on and lowest 12hrs later.
Observed at ZT00, 06, 12 and 18, per protein shows oscillation in the LP neurons and DN1a neurons under a 12:12 LD cycle. per protein is found in the nucleus at ZT23. Expression of per is variable in intensity in the DN1p neurons, the DN2 neurons and DN3 neurons at ZT23.
per protein shows strong oscillations under LD conditions, with a peak in the night and a gradual decrease at lights on. per protein is not restricted to the cytoplasm, but migrates to and from the nucleus.
per is lost from within the nucleus of the l-LNvs by ZT10. It is found to be evenly distributed between the nucleus and the cytoplasm at ZT16, four hours after lights-off. It becomes predominantly nuclear by ZT19 and remains so for the rest of the dark period. In the s-LNv neurons, per is restricted to the cytoplasm until ZT16, but is seen in both the cytoplasm and nucleus by ZT18, becoming predominantly nuclear by ZT20.
per protein in the adult is expressed in the s-LNv Pdf positive, l-LNv, LNd and DN neurons. On the third instar larval stage it is expressed in the larval s-LNv Pdf neurons.
Expression levels of per cycle in Malpighian tubules in a circadian pattern.
Period staining is strongest at ZT0-1, but is absent at ZT12. At peak expression, the Period protein is predominantly nuclear. tim protein colocalizes with the per protein.
A detailed examination of the distribution of per protein-expressing cells within the adult brain was made. Expression was detected in the ocelli, the photoreceptor cells, and throughout the central brain and the optic ganglia and the detailed locations of expressing cells were described. The most prominent immunoreactive cells are lateral cells in the cortical area between the inner margin of the medulla and the central brain neuropil which may correspond to the medullary tangential neurons. Double staining with an antibody to elav which recognizes only neurons was used to determine the nature of the per protein-expressing cells. The per protein-expressing cells in the ocelli and eyes, the lateral cells, and the dorsal-most cortex cells were shown to be neurons. The cells located at the margins of the cortex and neuropil in the optic lobes and the central brain, the cells within the lamina and central brain neuropil, and the cells in the inner chiasm are not neurons and are thought to be glia.
Marker for
Subcellular Localization
CV Term
Evidence
References
Expression Deduced from Reporters
Reporter: P{GAL4-per.BS}
Stage
Tissue/Position (including subcellular localization)
Reference
s-LNv neuron

Comment: Variably labelled between samples

DN2 neuron

Comment: Variably labelled between samples

LNd neuron

Comment: Variably labelled between samples

periesophageal neuropils | restricted

Comment: Cells surrounding the esophageal foramen

eye

Comment: faint expression

ellipsoid body

Comment: strong expression

glial cell of adult brain

Comment: faint expression

Reporter: P{per.8.0-luc}
Stage
Tissue/Position (including subcellular localization)
Reference
Reporter: P{per.XLG-luc}
Stage
Tissue/Position (including subcellular localization)
Reference
Reporter: P{per-lacZ.BG}
Stage
Tissue/Position (including subcellular localization)
Reference
larval LN period neuron

Comment: Expression was strong in 3-5 neurons at ZT23.

larval DN3 neuron

Comment: Staining only seen in 5% of brain hemispheres studied.

Reporter: P{per-lacZ.SG}
Stage
Tissue/Position (including subcellular localization)
Reference
Reporter: P{per-lexA.p65}
Stage
Tissue/Position (including subcellular localization)
Reference
Reporter: P{WF6}
Stage
Tissue/Position (including subcellular localization)
Reference
High-Throughput Expression Data
Associated Tools

GBrowse - Visual display of RNA-Seq signals

View Dmel\per in GBrowse 2
RNA-Seq by Region - Search RNA-Seq expression levels by exon or genomic region
Reference
See Gelbart and Emmert, 2013 for analysis details and data files for all genes.
Developmental Proteome: Life Cycle
Developmental Proteome: Embryogenesis
External Data and Images
Linkouts
FLIGHT - Cell culture data for RNAi and other high-throughput technologies
FlyAtlas - Adult expression by tissue, using Affymetrix Dros2 array
Fly-FISH - A database of Drosophila embryo and larvae mRNA localization patterns
Flygut - An atlas of the Drosophila adult midgut
Images
Alleles, Insertions, Transgenic Constructs and Phenotypes
Classical and Insertion Alleles ( 56 )
For All Classical and Insertion Alleles Show
 
Allele of per
Class
Mutagen
Associated Insertion
Stocks
Known lesion
    0
    Yes
      0
      Yes
        0
        Yes
          0
          Yes
            0
            Yes
              0
              Yes
                0
                Yes
                  0
                  --
                    0
                    --
                      0
                      --
                        0
                        --
                          0
                          --
                            0
                            --
                              0
                              Yes
                                0
                                Yes
                                  0
                                  Yes
                                    0
                                    Yes
                                      0
                                      Yes
                                        0
                                        Yes
                                          0
                                          Yes
                                            0
                                            Yes
                                              0
                                              Yes
                                                0
                                                Yes
                                                  0
                                                  Yes
                                                    0
                                                    Yes
                                                      0
                                                      Yes
                                                        0
                                                        Yes
                                                          0
                                                          Yes
                                                            0
                                                            Yes
                                                              0
                                                              Yes
                                                                0
                                                                Yes
                                                                  0
                                                                  Yes
                                                                  Other relevant insertions
                                                                  insertion of mobile activating element
                                                                  Name
                                                                  Expression Data
                                                                  Transgenic Constructs ( 169 )
                                                                  For All Alleles Carried on Transgenic Constructs Show
                                                                  Transgenic constructs containing/affecting coding region of per
                                                                  Allele of per
                                                                  Mutagen
                                                                  Associated Transgenic Construct
                                                                  Stocks
                                                                  Transgenic constructs containing regulatory region of per
                                                                  characterization construct
                                                                  GAL4 construct
                                                                  Name
                                                                  Expression Data
                                                                  vital-reporter construct
                                                                  Deletions and Duplications ( 31 )
                                                                  Partially duplicated in
                                                                  Summary of Phenotypes
                                                                  For more details about a specific phenotype click on the relevant allele symbol.
                                                                  Lethality
                                                                  Allele
                                                                  Sterility
                                                                  Allele
                                                                  Other Phenotypes
                                                                  Allele
                                                                  Phenotype manifest in
                                                                  Allele
                                                                  Orthologs
                                                                  Human Orthologs (via DIOPT v7.1)
                                                                  Homo sapiens (Human) (3)
                                                                  Species\Gene Symbol
                                                                  Score
                                                                  Best Score
                                                                  Best Reverse Score
                                                                  Alignment
                                                                  Complementation?
                                                                  Transgene?
                                                                  6 of 15
                                                                  Yes
                                                                  Yes
                                                                  5 of 15
                                                                  No
                                                                  Yes
                                                                  3 of 15
                                                                  No
                                                                  Yes
                                                                  Model Organism Orthologs (via DIOPT v7.1)
                                                                  Mus musculus (laboratory mouse) (3)
                                                                  Species\Gene Symbol
                                                                  Score
                                                                  Best Score
                                                                  Best Reverse Score
                                                                  Alignment
                                                                  Complementation?
                                                                  Transgene?
                                                                  6 of 15
                                                                  Yes
                                                                  Yes
                                                                  5 of 15
                                                                  No
                                                                  Yes
                                                                   
                                                                   
                                                                  5 of 15
                                                                  No
                                                                  Yes
                                                                   
                                                                   
                                                                  Rattus norvegicus (Norway rat) (3)
                                                                  5 of 13
                                                                  Yes
                                                                  Yes
                                                                  5 of 13
                                                                  Yes
                                                                  Yes
                                                                  4 of 13
                                                                  No
                                                                  Yes
                                                                  Xenopus tropicalis (Western clawed frog) (3)
                                                                  2 of 12
                                                                  Yes
                                                                  Yes
                                                                  2 of 12
                                                                  Yes
                                                                  Yes
                                                                  1 of 12
                                                                  No
                                                                  Yes
                                                                  Danio rerio (Zebrafish) (4)
                                                                  6 of 15
                                                                  Yes
                                                                  Yes
                                                                  5 of 15
                                                                  No
                                                                  Yes
                                                                  3 of 15
                                                                  No
                                                                  Yes
                                                                  3 of 15
                                                                  No
                                                                  Yes
                                                                  Caenorhabditis elegans (Nematode, roundworm) (3)
                                                                  4 of 15
                                                                  Yes
                                                                  Yes
                                                                  1 of 15
                                                                  No
                                                                  Yes
                                                                  1 of 15
                                                                  No
                                                                  Yes
                                                                  Arabidopsis thaliana (thale-cress) (0)
                                                                  No orthologs reported.
                                                                  Saccharomyces cerevisiae (Brewer's yeast) (0)
                                                                  No orthologs reported.
                                                                  Schizosaccharomyces pombe (Fission yeast) (0)
                                                                  No orthologs reported.
                                                                  Orthologs in Drosophila Species (via OrthoDB v9.1) ( EOG09190247 )
                                                                  Organism
                                                                  Common Name
                                                                  Gene
                                                                  AAA Syntenic Ortholog
                                                                  Multiple Dmel Genes in this Orthologous Group
                                                                  Drosophila melanogaster
                                                                  fruit fly
                                                                  Drosophila suzukii
                                                                  Spotted wing Drosophila
                                                                  Drosophila simulans
                                                                  Drosophila sechellia
                                                                  Drosophila erecta
                                                                  Drosophila ananassae
                                                                  Drosophila pseudoobscura pseudoobscura
                                                                  Drosophila willistoni
                                                                  Drosophila virilis
                                                                  Drosophila mojavensis
                                                                  Drosophila grimshawi
                                                                  Orthologs in non-Drosophila Dipterans (via OrthoDB v9.1) ( EOG0915010P )
                                                                  Organism
                                                                  Common Name
                                                                  Gene
                                                                  Multiple Dmel Genes in this Orthologous Group
                                                                  Musca domestica
                                                                  House fly
                                                                  Glossina morsitans
                                                                  Tsetse fly
                                                                  Lucilia cuprina
                                                                  Australian sheep blowfly
                                                                  Aedes aegypti
                                                                  Yellow fever mosquito
                                                                  Anopheles darlingi
                                                                  American malaria mosquito
                                                                  Orthologs in non-Dipteran Insects (via OrthoDB v9.1) ( EOG090W0L4R )
                                                                  Organism
                                                                  Common Name
                                                                  Gene
                                                                  Multiple Dmel Genes in this Orthologous Group
                                                                  Bombyx mori
                                                                  Silkmoth
                                                                  Bombyx mori
                                                                  Silkmoth
                                                                  Danaus plexippus
                                                                  Monarch butterfly
                                                                  Heliconius melpomene
                                                                  Postman butterfly
                                                                  Apis florea
                                                                  Little honeybee
                                                                  Apis mellifera
                                                                  Western honey bee
                                                                  Apis mellifera
                                                                  Western honey bee
                                                                  Bombus impatiens
                                                                  Common eastern bumble bee
                                                                  Bombus terrestris
                                                                  Buff-tailed bumblebee
                                                                  Linepithema humile
                                                                  Argentine ant
                                                                  Megachile rotundata
                                                                  Alfalfa leafcutting bee
                                                                  Nasonia vitripennis
                                                                  Parasitic wasp
                                                                  Dendroctonus ponderosae
                                                                  Mountain pine beetle
                                                                  Tribolium castaneum
                                                                  Red flour beetle
                                                                  Pediculus humanus
                                                                  Human body louse
                                                                  Rhodnius prolixus
                                                                  Kissing bug
                                                                  Cimex lectularius
                                                                  Bed bug
                                                                  Acyrthosiphon pisum
                                                                  Pea aphid
                                                                  Zootermopsis nevadensis
                                                                  Nevada dampwood termite
                                                                  Orthologs in non-Insect Arthropods (via OrthoDB v9.1) ( EOG090X0LBZ )
                                                                  Organism
                                                                  Common Name
                                                                  Gene
                                                                  Multiple Dmel Genes in this Orthologous Group
                                                                  Ixodes scapularis
                                                                  Black-legged tick
                                                                  Stegodyphus mimosarum
                                                                  African social velvet spider
                                                                  Tetranychus urticae
                                                                  Two-spotted spider mite
                                                                  Daphnia pulex
                                                                  Water flea
                                                                  Orthologs in non-Arthropod Metazoa (via OrthoDB v9.1) ( None identified )
                                                                  No non-Arthropod Metazoa orthologies identified
                                                                  Human Disease Model Data
                                                                  FlyBase Human Disease Model Reports
                                                                    Alleles Reported to Model Human Disease (Disease Ontology)
                                                                    Download
                                                                    Models ( 0 )
                                                                    Allele
                                                                    Disease
                                                                    Evidence
                                                                    References
                                                                    Interactions ( 1 )
                                                                    Allele
                                                                    Disease
                                                                    Interaction
                                                                    References
                                                                    Comments ( 0 )
                                                                     
                                                                    Human Orthologs (via DIOPT v7.1)
                                                                    Note that ortholog calls supported by only 1 or 2 algorithms (DIOPT score < 3) are not shown.
                                                                    Functional Complementation Data
                                                                    Functional complementation data is computed by FlyBase using a combination of the orthology data obtained from DIOPT and OrthoDB and the allele-level genetic interaction data curated from the literature.
                                                                    Dmel gene
                                                                    Ortholog showing functional complementation
                                                                    Supporting References
                                                                    Interactions
                                                                    Summary of Physical Interactions
                                                                    esyN Network Diagram
                                                                    Show neighbor-neighbor interactions:
                                                                    Select Layout:
                                                                    Legend:
                                                                    Protein
                                                                    RNA
                                                                    Selected Interactor(s)
                                                                    Interactions Browser

                                                                    Please look at the Interaction Group reports for full details of the physical interactions
                                                                    protein-protein
                                                                    Interacting group
                                                                    Assay
                                                                    References
                                                                    RNA-protein
                                                                    Interacting group
                                                                    Assay
                                                                    References
                                                                    Summary of Genetic Interactions
                                                                    esyN Network Diagram
                                                                    esyN Network Key:
                                                                    Suppression
                                                                    Enhancement

                                                                    Please look at the allele data for full details of the genetic interactions
                                                                    Starting gene(s)
                                                                    Interaction type
                                                                    Interacting gene(s)
                                                                    Reference
                                                                    Starting gene(s)
                                                                    Interaction type
                                                                    Interacting gene(s)
                                                                    Reference
                                                                    External Data
                                                                    Subunit Structure (UniProtKB)
                                                                    Forms a heterodimer with timeless (TIM); the complex then translocates into the nucleus. A proportion of the protein exists as homodimer.
                                                                    (UniProt, P07663 )
                                                                    Linkouts
                                                                    BioGRID - A database of protein and genetic interactions.
                                                                    DroID - A comprehensive database of gene and protein interactions.
                                                                    InterologFinder - Protein-protein interactions (PPI) from both known and predicted PPI data sets.
                                                                    Pathways
                                                                    Gene Group - Pathway Membership (FlyBase)
                                                                    External Data
                                                                    Linkouts
                                                                    Genomic Location and Detailed Mapping Data
                                                                    Chromosome (arm)
                                                                    X
                                                                    Recombination map
                                                                    1-1.5
                                                                    Cytogenetic map
                                                                    Sequence location
                                                                    X:2,685,580..2,692,780 [+]
                                                                    FlyBase Computed Cytological Location
                                                                    Cytogenetic map
                                                                    Evidence for location
                                                                    3B1-3B2
                                                                    Limits computationally determined from genome sequence between P{EP}EP1362 and P{EP}dncEP1395
                                                                    Experimentally Determined Cytological Location
                                                                    Cytogenetic map
                                                                    Notes
                                                                    References
                                                                    3B1-3B1
                                                                    (determined by in situ hybridisation)
                                                                    3B1-3B2
                                                                    (determined by in situ hybridisation)
                                                                    Experimentally Determined Recombination Data
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                                                                    1-1.2
                                                                    Stocks and Reagents
                                                                    Stocks (22)
                                                                    Genomic Clones (28)
                                                                    cDNA Clones (32)
                                                                     

                                                                    Please Note This section lists cDNAs and ESTs that fall within the genomic extent of the gene model, which may include cDNAs and ESTs of genes within introns, or of overlapping genes. Please see GBrowse for alignment of the cDNAs and ESTs to the gene model.

                                                                    cDNA clones, fully sequences
                                                                    BDGP DGC clones
                                                                      Other clones
                                                                      Drosophila Genomics Resource Center cDNA clones

                                                                      For each fully sequenced cDNA the DGRC maintains various forms of the cDNA (e.g tagged or untagged) in several different host vectors for subsequent cloning and expression in Drosophila and Drosophila cell lines.

                                                                      cDNA Clones, End Sequenced (ESTs)
                                                                      RNAi and Array Information
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                                                                      GenomeRNAi - A database for cell-based and in vivo RNAi phenotypes and reagents
                                                                      Antibody Information
                                                                      Other Information
                                                                      Relationship to Other Genes
                                                                      Source for database identify of
                                                                      Source for identity of: per CG2647
                                                                      Source for database merge of
                                                                      Additional comments
                                                                      Other Comments
                                                                      Delayed per entry into the nucleus correlates with an increase in period length.
                                                                      DNA-protein interactions: genome-wide binding profile (ChIP-chip) assayed for per protein in adult heads; see GEO_GSE32613 (http://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE32613).
                                                                      Gene expression is increased in response to the presence of two copies of Scer\GAL4hs.PB.
                                                                      per is required for entrainment of the circadian clock by temperature.
                                                                      per is necessary for nuclear localization of tim.
                                                                      Nuclear transport is essential for the inhibitory action of per.
                                                                      Shows particularly robust cycling of transcription in adult heads, as assessed by expression analysis using high density oligonucleotide arrays with probe generated during three 12-point time course experiments over the course of 6 days.
                                                                      Identified as one of 10 highest fold cycling genes as assessed by expression analysis using high density oligonucleotide arrays with probe generated from adult heads harvested over six time points over the course of a day.
                                                                      per has a role in circadian mating rhythm regulation.
                                                                      Maintenance of the per-tim feedback loop is not an absolute requirement for behavioral rhythms, but cyclic expression of the two proteins is essential.
                                                                      per dependent molecular oscillators may have a role in the modulation of amine receptor responsiveness.
                                                                      "Gene order: Overall orientation not stated: per+ CG2650- CG2658- Csat-" was stated as revision.
                                                                      Excretory organs exhibit autonomous per and tim cycling.
                                                                      Light and post-transcriptional regulation play major roles in defining the temporal properties of the per and tim protein curves. The lag between mRNA and protein accumulation is unecessary for the feedback regulation of per and tim protein on per and tim transcription.
                                                                      Sensitization to repeated cocaine exposures, a phenomenon also seen in humans and animal models and associated with enhanced drug craving, is eliminated in flies mutant for per, dco, Clk, and cyc but not tim.
                                                                      per, along with other circadian genes Clk, cyc, and dco (but not tim) have roles in regulating cocaine sensitization and may function as regulators of Tdc.
                                                                      Mutants in per genes effect CrebB-17A activity, suggesting that the two genes participate in the same regulatory feedback loop.
                                                                      The cry gene product blocks the function of the per/tim heterodimeric complex in a light-dependent fashion.
                                                                      Clk mRNA cycling is regulated by per-tim-mediated release of Clk- and cyc-dependent repression.
                                                                      Mutations in per abolish circadian rhythms in olfactory responses.
                                                                      Daily cycles in the association of per and tim proteins with the Clk-cyc complex may contribute to rhythmic expression of per and tim.
                                                                      A thermosensitive splicing event in the 3' UTR of the per mRNA plays an important role in how the circadian clock adapts to seasonally cold days. Enhanced splicing at cold temperatures advances the steady state phases of the per mRNA and protein cycles, contributing to the preferential day time activity of flies on cold days. There is a temperature-dependent switch in the molecular logic governing cycles in per mRNA levels.
                                                                      timrit lengthens circadian period in a temperature-dependent manner through suppression of per protein cycling and nuclear localization.
                                                                      tim increases per mRNA levels through a post-transcriptional mechanism.
                                                                      per controls courtship song cycles.
                                                                      Photoreceptors R1-R6 contain an autonomous circadian oscillator that can function without per mRNA cycling.
                                                                      per mRNA cycling is not required for per protein cycling.
                                                                      Transcription of per and tim, inhibitors if Clk, is induced by Clk.
                                                                      Study of per and Dpse\per fusions reveals striking phenotypic differences between transgenic flies, these difference support the idea of an intragenic coevolution between the repeat and flanking regions of the two genes.
                                                                      The gene product of the dco locus regulates per protein accumulation. The function of dco may be to reduce the stability and thus the level of accumulation of monomeric per proteins, promoting the delay between per/tim transcription and the function of the per/tim protein complex, which is essential for molecular rhythmicity.
                                                                      Mutations at the per locus do not influence mean courtship duration.
                                                                      Heat pulses at all times in a daily cycle elicited dramatic and rapid decreases in the levels of per and tim proteins, the proteins can be independently degraded by heat pulses. These two modalities produce markedly different long term effects on the circadian time-keeping mechanism. Heat-induced phase delays in behavioural rhythms are accompanied by long-term delays in the per and tim biochemical oscillations. Heat pulses in the late night elicit transient and rapid increases in the speed of the per-tim cycles. The timing of per and tim mRNA cycles is perturbed by heat pulses in a manner consistent with the direction and magnitude of the behavioural phase shift.
                                                                      per coding region contains posttrancriptional regulatory information that is important for per protein cycling.
                                                                      per protein expression in the pupal prothoracic gland has been studied in vivo and in ring glands cultured in vitro.
                                                                      A circadian transcriptional enhancer within a 69bp DNA fragment is identified in per upstream sequences. The enhancer drives high-amplitude mRNA cycling under light-dark-cycling or constant-dark conditions and this activity is per protein-dependent. An E-box sequence within this fragment is necessary for high-level expression, but not for rhythmic expression, indicating per mediates circadian transcription through other sequences in this fragment.
                                                                      Analysis of the rhythmic expression of a per reporter construct suggests that the Malpighian tubules contain a circadian pacemaker that functions independently of the brain.
                                                                      The products of per and tim are detectable in a limited number of neurons in the larval CNS, the expression patterns in several such cells is cyclical.
                                                                      The temporal regulation of per protein and RNA products is used to evaluate the status of the oscillatory mechanism in Pka-C1 mutants and to determine the site of action on the circadian timing system that is affected by reduced levels of Pka-C1.
                                                                      per driven Ppyr\LUC reporter gene expression can be used to investigate transcriptional regulation of per and allows study of the molecular rhythmicity of an individual fly.
                                                                      Quantifying rates of protein sequence divergence within and between species reveals that the Drosophila genome harbors a substantial proportion of genes with a very high divergence rate.
                                                                      Nuclear run-on assays for fly heads and the in vivo transcription rate of per and tim suggest that there is an important circadian regulation at a post-transcriptional level. Results suggest this additional regulatory mode serves to ensure proper circadian fluctuations of clock gene expression.
                                                                      A new regulatory element necessary for the correct temporal expression of per is identified by monitoring real-tie per expression in living individual flies carrying two different per-Ppyr\LUC transgenes.
                                                                      The spatial and temporal expression patterns of per-Ecol\lacZ constructs containing differing amounts of the per coding region have been analysed.
                                                                      Circadian rhythms are clearly exhibited in constant darkness even in flies reared in constant light and constant darkness as well as flies reared in light-dark cycles, but the freerunning period differs. Results suggest that the circadian clock is assembled without any cyclical photic information and light influences the developing circadian clock to alter the freerunning period.
                                                                      A Ppyr\LUC reporter construct permits per circadian rhythms to be monitored by bioluminescence over several days in living adults and reveals novel features of per transcription.
                                                                      Nuclear expression of tim depends on per. The expression of tim, but not per, is rapidly reduced by light, suggesting that tim mediates light-induced resetting of the circadian clock.
                                                                      Photic stimuli perturb the timing of the per protein and mRNA cycles in a manner consistent with the direction and magnitude of the phase shift. The tim protein interacts with per in vivo, and the association is rapidly decreased by light. The disruption of the per-tim complex in the cytoplasm is accompanied by a delay in per phosphorylation and nuclear entry and disruption in the nucleus by an advance in per phosphorylation and disappearance.
                                                                      Light inhibits the level and phosphorylation status of per and tim proteins, this then delays the negative feedback circuit (in which per or the per-tim complex participates) and extends the RNA profiles. This light-mediated delay compensates for the accelerated RNA increase in per mutant strains and restores rhythms to wild-type like periodicities.
                                                                      The tim and per proteins physically interact and the timing of their association and nuclear localization promotes cycles of per and tim transcription through an autoregulatory feedback loop. tim couples the per-tim pacemaker to the environment: the tim gene product is rapidly degraded on exposure to light.
                                                                      Studies of per mRNA cycling and locomotor activity rhythms under different light/dark cycling regimes indicate that the per feedback loop uses lights-off as a phase reference point and suggest that per mRNA cycling is not regulated via simple negative feedback from the per protein.
                                                                      The complete sequence of the Thr-Gly region is examined and reveals that the region has evolved largely by the action of deletions/duplications and point mutations. Polymorphic sites upstream and downstream of the Thr-Gly region are also examined.
                                                                      The identification of a period-altering tim allele provides further evidence that tim is a major component of the clock, and the allele-specific interactions with per provide evidence that the per/tim heterodimer is a unit of circadian function.
                                                                      tim and per accumulate in the cytoplasm when independently expressed in S2 cells and move to the nucleus when coexpressed. Domains of per and tim have been identified that block nuclear localisation of the monomeric proteins. In vitro protein interaction studies indicate that the sequence inhibiting the nuclear accumulation of per forms a binding site for tim. Results indicate a mechanism for controlled nuclear localisation in which suppression of cytoplasmic localisation is accomplished by direct interaction of per and tim.
                                                                      per and tim are in a large protein complex, they are heterodimeric partners.
                                                                      The conformation of (Thr-Gly)n peptides (the conserved (Thr-Gly)n repeat in the per gene may have an important role in the temperature compensation of the circadian clock) has been analysed.
                                                                      Key pacemaker neurons of the brain were examined to determine the changes of subcellular distribution of per with the time of day, per accumulates in the cytoplasm for several hours before entering the nucleus during a narrow time window. Long-period mutations cause a delay in the timing of nuclear translocation and a further delay at elevated temperature. This data indicates that regulation of per nuclear entry is critical for circadian oscillations by providing a necessary temporal delay between per synthesis and its effect on transcription.
                                                                      The interaction between the tim and per products determines the timing of per nuclear entry and therefore the duration of part of the circadian cycle.
                                                                      Identification: as a protein that interacts specifically with per protein in a yeast two-hybrid assay.
                                                                      The entire arborisation pattern of per-containing pacemaker cells is revealed by immunostaining with crustacean pigment-dispersing hormone (PDH) antiserum. The arborisations of these neurons are appropriate for the modulation of the activity of many neurons and they might interact with per containing glial cells.
                                                                      Temperature compensation of circadian period may be due in part to temperature-independent PER activity, which is based on competition between inter- and intramolecular interactions with similar temperature coefficients.
                                                                      The period protein from the silkmoth A.pernyi can mediate clock functions in D.melanogaster.
                                                                      tim and per interact and both are required for production of circadian rhythms. Absence of tim sequence similarity to the PER dimerization motif (PAS) indicates that direct interaction between the per and tim products would require a heterotypic protein association.
                                                                      Mutations of tim lead to loss of circadian rhythms. tim suppresses circadian oscillations of per abundance and phosphorylation in light/dark cycles, depresses levels of per and blocks nuclear localisation of a per reporter gene due to a primary affect on per expression at the post-transcriptional level. Constant light has no effect on per in tim flies.
                                                                      A linear relationship between temperature compensation and per Thr-Gly repeat length has been demonstrated. The major natural variants differ by units of (Thr-Gly)3, and rarer variants whose lengths fall out of phase with this pattern show more erratic temperature compensation, providing a correlation between behaviour and protein structure. Interspecific comparisons reveal a co-evolutionary process between the Thr-Gly region and flanking regions.
                                                                      The tim RNA oscillations are dependent on the presence of per and tim proteins. The cyclic expression of tim appears to dictate the timing of per protein accumulation and nuclear localization, suggesting that tim promotes circadian rhythms of per and tim transcription by restricting per RNA and protein accumulation to separate times of day.
                                                                      DNA binding coimmunoprecipitation assays studying the interaction of human Arnt with other PAS proteins demonstrates human Arnt forms heterodimers with per and sim, by means of the PAS domain, in a cooperative way.
                                                                      Expression of per under the control of the gl promoter confers both behavioral and molecular rhythmicity. Expression in a few central brain cells producing gl and per product are capable of generating biological rhythms.
                                                                      Ecol\lacZ reporter gene constructs demonstrate that per contains multipartite regulatory information for dosage compensation within the first large intron and also within the 3' half of the locus.
                                                                      The per protein undergoes daily oscillations in apparent molecular mass and abundance. The mobility changes are exclusively due to multiple phosphorylation events, phosphorylation is an important determinant in the clock time keeping mechanism.
                                                                      Ectopic expression of per supports the contention that the per gene product is a clock component.
                                                                      Analysis of per mRNA cycling suggests that circadian oscillators are present in head and body tissues in which per protein is nuclear, and that these oscillators behave differently.
                                                                      A hypothesis has been suggested that a controlled chaotic attractor may provide the central oscillator responsible for the generation of circadian and ultradian rhythms. this can be tested by seeking chaotic dynamics in systems where the controls have been disrupted.
                                                                      The "Thr-Gly" region of the per gene has been compared with the corresponding region of the per genes of a number of Dipteran species.
                                                                      The process of reinitiation of a 24 hour rhythmicity in individual flies reared in constant darkness (DD) is studied.
                                                                      D.melanogaster females do not discriminate between males carrying D.melanogaster or D.simulans per genes, indicating that the per locus may only make a small contribution to total premating isolation between the two species.
                                                                      per gene does not influence an observable locomotor behavioural phenotype in the larval stage of development.
                                                                      per gene contains sequences that can inhibit per protein nuclear localisation in the absence of tim protein.
                                                                      Autoregulation of per transcription is a direct, intracellular event and each per expressing cell may contain an autonomous clock, of which the per autoregulation loop is a component.
                                                                      Sequences homologous to per demonstrated in the genome of the mole rat, Spalax ehrenbergi.
                                                                      Protein-protein interactions mediated through the PAS domain may be a crucial aspect of per biochemical function.
                                                                      The per gene contains an amino acid motif of approximately 270 residues, termed PAS, whose function is unknown. PAS is also present in sim gene product, and in the two subunits of the mammalian dioxin receptor. Coprecipitation experiments showed that PAS functions in vitro as a novel protein dimerization motif which can mediate interactions between different members of the PAS protein family. Missense mutations in the PAS domain, including the original perL1, decrease the dimerization efficiency. In vivo experiments using transformants with tagged per coding regions suggest that dimerization also occurs in vivo.
                                                                      A 1.9 kb region of per has been compared in D.melanogaster, D.simulans, D.sechellia and D.mauritiana, and reveals a complex history. D.simulans appears to be a parent species to D.sechellia and D.mauritiana, but the order of appearance of the two species remains unclear. Whereas D.simulans and D.mauritiana share a large number of polymorphisms, D.sechellia shows very little variation.
                                                                      Validity of experiments that led to the conclusions that strong differences in intercellular coupling distinguished per genotypes have been called into question. A reinvestigation of dye coupling concluded that no consistent differences in intercellular coupling in salivary glands can be attributed to mutations at the per lous (Flint, Rosbash and Hall, and Spray and Siwicki, unpublished information).
                                                                      Mutations altering the structure of an approximately 20 amino acid segment, surrounding the location of the pers mutation, confer short per phenotypes. Loss or lowered function may dramatically increase measured level of protein activity.
                                                                      Mutants exhibit defective courtship song.
                                                                      Effects of per mutant alleles on visual pigment, sensitivity and rhabdomere size in 12hr light/12hr dark cycles was measured.
                                                                      Minisatellite region encoding thr-gly repeat is polymorphic in length in natural populations. Geographical analysis of this polymorphism cloned by PCR reveals a robust clinal pattern observed along a north-south axis: the higher the latitude the more likely a population is to have thr-gly20 and less likely to have thr-gly17. Length polymorphism may be maintained by thermal selection, because thr-gly region has been shown to provide thermostability to the circadian phenotype.
                                                                      A 13.2kb construct cloned from Clk-bearing flies will rescue arrhythmicity of per mutants. Transformant flies have shorter than normal rhythms demonstrating that the Clk mutation is within the 13.2b per fragment.
                                                                      Internally marked mosaics determined that the pacemaker location is in the brain but not exclusively in the eyes, optic lobe or the ocelli. Although the pacemaker may be paired, the function of one of them is sufficient for rhythmicity. Glial expression is sufficient for some, albeit weak, rhythmicity.
                                                                      Courtship song rhythms and locomotor activity rhythms assayed in D.melanogaster carrying Dsim\per or D.melanogaster/D.simulans per gene fusions. In all cases the circadian periodicities were slightly longer than for wild type, suggesting that the 13.2kb per fragment used to make the transgenic constructs is slightly inadequate at performing wild type per function.
                                                                      Phases of the evening peaks of activity under LD conditions are correspondingly earlier than normal for the short-period mutants and later than normal for long cycle durations. The morning peaks, however, move minimally under the influence of a given per variant.
                                                                      Fluctuations in per mRNA are primarily controlled by fluctuations in per transcription: per mRNA has a relatively short half life, and sequences sufficient to drive per mRNA cycling are present in 1.3kb of 5' flanking sequences.
                                                                      per protein is found predominantly in the nuclei in adult Drosophila.
                                                                      Mutagenesis of the per gene product reveals that the only the presence of a serine at residue 589 gives a 24h period but mutation of position 589 gives short period mutants. These short period mutants give rise to pacemakers with elements that fail to respond to the negative feedback loops of circadian oscillators.
                                                                      The threonine-glycine encoding repeat region of the per gene shows high levels of length polymorphism in natural populations of D.melanogaster.
                                                                      Associative learning of per mutants is assayed using the classical conditioning procedure of Tully (FBrf0043081). Results lend little support to the possibility that a short-cycle oscillation plays an integral role in learning processes; neither do they indicate any general effect on learning attributable to an abnormally lengthened circadian rhythm.
                                                                      Chimeric per gene constructs from D.melanogaster and D.simulans have been used to map the genetic control of their courtship song rhythm difference to a small segment of the amino acid encoding information within per.
                                                                      Ectopic expression of per demonstrates that per gene action during preimaginal stages is neither necessary or sufficient for locomotor activity rhythms to be expressed in the adult. per gene function appears to be necessary for pacemaker functioning itself. By analysing the singing of D.simulans and D.melanogaster reciprocally hybrid males the genetic etiology of the song rhythm difference is due to 1-4 amino acid replacements that have occurred over evolutionary time.
                                                                      per mRNA levels in the fly head undergo circadian fluctuations during both 12 hour light/12 hour dark cycles and constant darkness.
                                                                      The rhythmic components of male courtship songs have been spectral analysed.
                                                                      The per gene product is thought to be involved in the regulation of the cell cycle as per mutant development time differs from wild type. A role of per in timers required for conditioning is suggested as mutations can slow down the biological timers. Transformation experiments involving the Thr-Gly encoding region of per (Yu, Nature 326:765 ) suggest that the Thr-Gly residues may play a role in determining song cycles, per has 17 to 23 Thr-Gly pairs and sings with 55 second song cycles.
                                                                      Fluctuations in per protein expression in the visual system and central brain of adult flies at different times of the day have been studied.
                                                                      per has an indirect influence on the levels of CG2650 transcript via its own regulation of eclosion rhythm.
                                                                      Sequence analysis of frequency (frq) of N.crassa identifies a common element between frq and per suggesting a common element in the clock mechanisms of these two organisms.
                                                                      Aberrant intervals between song pulses were observed in per mutant songs.
                                                                      Comparison of the predicted protein sequence of the Thr-Gly repeat region of different D.melanogaster strains reveals a high degree of polymorphism and evolutionary plasticity. Deletion derivatives of the per gene lacking all the perfect Thr-Gly repeats indicates that the Thr-Gly region may have an important function in the courtship song phenotype.
                                                                      The lesions associated with per01 and pers have been molecularly mapped.
                                                                      per has been cloned and sequenced.
                                                                      Germ line transformation demonstrates that a 7.1kb fragment including the per transcript can restore rhythmicity of eclosion and activity to per mutants.
                                                                      per01 is complemented by l(1)3A and l(1)3B mutants nearby (Young and Judd, 1978; Smith and Konopka, 1981). The mutant per01 of D.melanogaster can be rescued (i.e. made to show rhythmic behavior) by transformation with a hybrid gene carrying the coding region of the D.pseudoobscura.pseudoobscura per gene (Peterson et al., 1988).
                                                                      The per gene is essential for biological clock functions and determines the period length of circadian and ultradian rhythms. The per mutants are characterized by aberrant rhythms involving eclosion and locomotor activity (Konopka and Benzer, 1971) and may change the rhythmic component of the male courtship song (Crossley, 1988; Ewing, 1988; Kyriacou and Hall, 1980, 1986, 1988). These mutants also affect the rhythm of the larval heartbeat (Dowse, Ringo and Kyriacou) (Livingstone, 1981), the level of tyrosine decarboxylase (Livingstone and Tempel, 1983) and fluctuations in membrane potentials in larval salivary glands (Weitzel and Rensing, 1981), modulate intercellular junctional communication (Bargiello et al., 1987), and alter the location of neural secretory cells in the brain (Konopka and Wells, 1980). In wild-type flies the period length is about 24 hr. In general, increases in per+ dosage lead to shortened circadian rhythms and decreases lead to lengthened circadian rhythms (Baylies et al., 1987; Cote and Brody, 1986; Hamblen et al., 1986; Smith and Konopka, 1981; Smith and Konopka, 1982; Young et al., 1985). Females heterozygous for per+ and a deletion of the locus or a per01 allele show longer-than-normal periods. per flies can be classified on the basis of their circadian rhythms as: (1) Cryptic period mutants (per01, per-) which have a 10-15 hr (ultradian) period and appear arrhythmic except in special algorhythmic tests (Dowse, Hall and Ringo, 1987); (2) Long period mutants (perL), 29 hr; (3) Long-period variable mutants (perLvar), which in homozygotes or heterozygotes are arrhythmic but in combination with certain partial deletions of the per locus result in a 30-34 hr period (Konopka, 1987); (4) Short period mutants (pers), 19 hr; (5) Short period variable mutants (persvar), some flies having a 20 hr period and the others a normal 24 hr period for locomotor activity. In temperature-change experiments on pers and perL1, the locomotor activity periods were found to be nearer to 24 hr at low temperatures, but to diverge further from normal upon heating (Konopka, Pittendrigh, and Orr, 1989; Hamblen, Ewer and Hall). perL2 shows lengthening of the periods at high temperatures. The mutant types affecting circadian rhythms (per01, perL1 and pers) may cause similar kinds of changes in the rhythmic fluctuations in courtship song interpulse intervals (IPIs) of the male (Crossley, 1988; Ewing, 1988; Kyriacou and Hall, 1980; Kyriacou and Hall, 1986; Kyriacou and Hall, 1988). per01 mutants show nonrhythmic variations in the interval between pulses of wing vibration. Neural studies show that transplantation of pers brains into per01 adult hosts causes some of the hosts to be 'rescued'; i.e. to show short-period circadian rhythms for locomotor activity (Handler and Konopka, 1979). Octopamine synthesis occurs at subnormal rates in per01 brains, with a corresponding decrease in the enzyme tyrosine decarboxylase (Livingstone and Tempel, 1983); less severe decrements in tyrosine decarboxylase are found in pers and perL1 flies. Physiological studies that claimed that per mutations can affect the level of gap junctional communication among cells in a tissue (Bargiello et al., 1987). In salivary glands and that the per01 and perL1 mutations cause a lowering of the level of junctional communication have been withdrawn (Saez, Young, Baylies, Gasic, Bargiello and Spray, 1992). Mosaic analysis of pers mutants indicates that the gene influences the brain with respect to aberrant locomotor rhythms (Konopka, Wells and Lee, 1983); per01 and per02 (and, to a lesser degree, pers) are said to cause anomalous photonegative behavior in light-response tests (Palmer, Kendrick, and Hotchkiss, 1985), but in general are not defective in visual responses (phototaxis tests, optomotor behavior and electroretinogram) according to Dushay and Hall.
                                                                      Origin and Etymology
                                                                      Discoverer
                                                                      Konopka.
                                                                      Etymology
                                                                      Identification
                                                                      External Crossreferences and Linkouts ( 226 )
                                                                      Crossreferences
                                                                      NCBI Gene - Gene integrates information from a wide range of species. A record may include nomenclature, Reference Sequences (RefSeqs), maps, pathways, variations, phenotypes, and links to genome-, phenotype-, and locus-specific resources worldwide.
                                                                      RefSeq - A comprehensive, integrated, non-redundant, well-annotated set of reference sequences including genomic, transcript, and protein.
                                                                      UniProt/Swiss-Prot - Manually annotated and reviewed records of protein sequence and functional information
                                                                      UniProt/TrEMBL - Automatically annotated and unreviewed records of protein sequence and functional information
                                                                      Other crossreferences
                                                                      InterPro - A database of protein families, domains and functional sites
                                                                      KEGG Pathways - Wiring diagrams of molecular interactions, reactions and relations.
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                                                                      Drosophila Genomics Resource Center - Drosophila Genomics Resource Center cDNA clones
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                                                                      Eukaryotic Promoter Database - A collection of databases of experimentally validated promoters for selected model organisms.
                                                                      FLIGHT - Cell culture data for RNAi and other high-throughput technologies
                                                                      FlyAtlas - Adult expression by tissue, using Affymetrix Dros2 array
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                                                                      Reactome - An open-source, open access, manually curated and peer-reviewed pathway database.
                                                                      GenomeRNAi - A database for cell-based and in vivo RNAi phenotypes and reagents
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                                                                      Synonyms and Secondary IDs (19)
                                                                      Reported As
                                                                      Symbol Synonym
                                                                      PER
                                                                      (Beck et al., 2018, Krzeptowski et al., 2018, Pilorz et al., 2018, Schlichting et al., 2018, Top and Young, 2018, Top et al., 2018, Xue and Zhang, 2018, Agrawal et al., 2017, Dubowy and Sehgal, 2017, Lee et al., 2017, Liu et al., 2017, Mendoza-Viveros et al., 2017, Chen and Rosbash, 2016, Ito and Tomioka, 2016, Top et al., 2016, Yoshii et al., 2016, Fan et al., 2015, Kang et al., 2015, Ki et al., 2015, Lerner et al., 2015, Liu et al., 2015, Anderson and Adolphs, 2014, Cavanaugh et al., 2014, Tataroglu and Emery, 2014, Anonymous, 2013, Erion and Sehgal, 2013, Garbe et al., 2013, Górska-Andrzejak, 2013, Hermann et al., 2013, Lim and Allada, 2013, Menegazzi et al., 2013, Ozturk et al., 2013, Szabó et al., 2013, Zhang et al., 2013, Beuchle et al., 2012, Jepson et al., 2012, Luo and Sehgal, 2012, Mandilaras and Missirlis, 2012, Risau-Gusman and Gleiser, 2012, Abruzzi et al., 2011, Chen et al., 2011, Depetris-Chauvin et al., 2011, Gatto and Broadie, 2011, Goda et al., 2011, Hara et al., 2011, King et al., 2011, Lan and Mezić, 2011, Weber et al., 2011, Im and Taghert, 2010, Ko et al., 2010, Zhang et al., 2010, Zhang et al., 2010, Zheng and Sehgal, 2010, Picot et al., 2009, Shafer and Taghert, 2009, Xu and Cai, 2009, Yoshii et al., 2009, Zhang et al., 2009, Berni et al., 2008, Koh et al., 2008, Sehgal, 2008, Sheeba et al., 2008, Bachleitner et al., 2007, de la Paz Fernandez et al., 2007, Hemsley et al., 2007, Kuczenski et al., 2007, Sandrelli et al., 2007, Veleri et al., 2007, Wang et al., 2007, Zheng et al., 2007, Collins et al., 2006, Dunlap, 2006, Houl et al., 2006, Meyer et al., 2006, Meyer et al., 2006, Rieger et al., 2006, Yu et al., 2006, Nitabach et al., 2005, Lin et al., 2004, Nawathean and Rosbash, 2004, Schroeder et al., 2003, Johnson and Day, 2000, Leloup and Goldbeter, 2000)
                                                                      clk-6
                                                                      per
                                                                      (Beck et al., 2018, Filošević et al., 2018, Fropf et al., 2018, Giebultowicz, 2018, Górska-Andrzejak et al., 2018, Noreen et al., 2018, Top et al., 2018, Yadlapalli et al., 2018, Young, 2018, Zhang et al., 2018, Abruzzi et al., 2017, Agrawal et al., 2017, Allen et al., 2017, Fujii et al., 2017, Harper et al., 2017, He et al., 2017, Kim et al., 2017, Kyriacou et al., 2017, Li et al., 2017, Li et al., 2017, Long and Giebultowicz, 2017, Park et al., 2017, Roessingh and Stanewsky, 2017, Zhao and Karpac, 2017, Allen et al., 2016, Barber et al., 2016, Cho et al., 2016, De Nobrega and Lyons, 2016, Di Cara and King-Jones, 2016, Fischer et al., 2016, Kim et al., 2016, Kučerová et al., 2016, Landgraf et al., 2016, Lazopulo and Syed, 2016, Liao et al., 2016, Lone et al., 2016, Maurer et al., 2016, Nikhil et al., 2016, Vaccaro et al., 2016, Zhang et al., 2016, Andreazza et al., 2015, Cao and Edery, 2015, Chen et al., 2015, Donelson and Sanyal, 2015, Flourakis et al., 2015, Giebultowicz and Long, 2015, Gill et al., 2015, Green et al., 2015, Grotewiel and Bettinger, 2015, Hales et al., 2015, Head et al., 2015, Jang et al., 2015, Jaumouillé et al., 2015, Kidd et al., 2015, Lazopulo et al., 2015, Lerner et al., 2015, Lin et al., 2015, Maguire and Sehgal, 2015, Means et al., 2015, Merbitz-Zahradnik and Wolf, 2015, Montelli et al., 2015, Nieto et al., 2015, Pasco et al., 2015, Petsakou et al., 2015, Roberts et al., 2015, Sakata et al., 2015, Tataroglu and Emery, 2015, Thimgan et al., 2015, Tomita et al., 2015, Zwarts et al., 2015, Barclay et al., 2014, Chen et al., 2014, Goda et al., 2014, Guo et al., 2014, Hermann-Luibl et al., 2014, Huang et al., 2014, Kumar et al., 2014, Lee et al., 2014, Li et al., 2014, Liu et al., 2014, Long et al., 2014, Mahesh et al., 2014, Pegoraro et al., 2014, Seluzicki et al., 2014, Shi et al., 2014, Subramanian et al., 2014, Taylor et al., 2014, Vrailas-Mortimer et al., 2014, Weiss et al., 2014, Yao and Shafer, 2014, Zheng et al., 2014, Ahmad et al., 2013, Bartok et al., 2013, Beckwith et al., 2013, Billeter and Levine, 2013, Costa and Stanewsky, 2013, De et al., 2013, Erion and Sehgal, 2013, Garbe et al., 2013, Ghezzi et al., 2013, Górska-Andrzejak, 2013, Itoh et al., 2013, Kaasik et al., 2013, Krupp et al., 2013, Lee et al., 2013, Li and Rosbash, 2013, Lim and Allada, 2013, Mehta and Cheng, 2013, Pandey et al., 2013, Pohl et al., 2013, Rakshit et al., 2013, Riveron et al., 2013, Rodriguez et al., 2013, Yamamoto and Ishikawa, 2013, Zhang and Emery, 2013, Zhang et al., 2013, Bywalez et al., 2012, Chen et al., 2012, De et al., 2012, Grima et al., 2012, Ishimoto et al., 2012, Japanese National Institute of Genetics, 2012.5.21, Kaneko et al., 2012, Kaun et al., 2012, Krishnan et al., 2012, Laturney and Moehring, 2012, Ling et al., 2012, Luo et al., 2012, Mizrak et al., 2012, Mukherjee et al., 2012, Pezzulo et al., 2012, Rakshit et al., 2012, Ruben et al., 2012, Sakai et al., 2012, Tanenhaus et al., 2012, Vanin et al., 2012, Vodala et al., 2012, Xu et al., 2012, Yoshihara and Ito, 2012, Abruzzi et al., 2011, Chiu et al., 2011, Diangelo et al., 2011, DiTacchio et al., 2011, Goda et al., 2011, Hara et al., 2011, Ito et al., 2011, Itoh et al., 2011, Kolaczkowski et al., 2011, Lamaze et al., 2011, Lim et al., 2011, Linde and Lyons, 2011, Lone and Sharma, 2011, Lone and Sharma, 2011, Lone et al., 2011, Mehnert and Cantera, 2011, Miller et al., 2011, Napoletano et al., 2011, Ng et al., 2011, Oliveira et al., 2011, Saez et al., 2011, Scribner and Fathallah-Shaykh, 2011, Stavropoulos and Young, 2011, Syed et al., 2011, Barth et al., 2010, Beaver et al., 2010, Blanchard et al., 2010, Chatterjee et al., 2010, Fathallah-Shaykh, 2010, Fernández-Ayala et al., 2010, Fujii and Amrein, 2010, Kula-Eversole et al., 2010, Kuo et al., 2010, Li et al., 2010, Menet et al., 2010, Nagoshi et al., 2010, Pereanu et al., 2010, Ruiz et al., 2010, Thimgan et al., 2010, van der Linde et al., 2010, Xie et al., 2010, Zhang et al., 2010, Zhang et al., 2010, Akten et al., 2009, Currie et al., 2009, Cusumano et al., 2009, Donlea et al., 2009, Fathallah-Shaykh et al., 2009, Górska-Andrzejak et al., 2009, Hung et al., 2009, Hung et al., 2009, Johard et al., 2009, Kadener et al., 2009, Kempinger et al., 2009, Kilman and Allada, 2009, Kilman et al., 2009, Kotwica et al., 2009, Krishnan et al., 2009, Landskron et al., 2009, Larsen et al., 2009, Lear et al., 2009, Lyons and Roman, 2009, Mohammad et al., 2009, Ni et al., 2009, Rieger et al., 2009, Sehadova et al., 2009, Shahidullah et al., 2009, Weber et al., 2009, Yu et al., 2009, Zheng et al., 2009, Anaka et al., 2008, Bagheri et al., 2008, Benito et al., 2008, Cao and Nitabach, 2008, Chiu et al., 2008, Dunlap, 2008, Fernandez et al., 2008, Fujii et al., 2008, Hodge and Stanewsky, 2008, Houl et al., 2008, Ito et al., 2008, Kadener et al., 2008, Kaiser and Cobb, 2008, Kivimäe et al., 2008, Krishnan et al., 2008, Krishnan et al., 2008, Krupp et al., 2008, Lee and Edery, 2008, Li and Lang, 2008, Liu and Lehmann, 2008, Lu et al., 2008, McDermott and Kliman, 2008, Meissner et al., 2008, Miura et al., 2008, Ogawa et al., 2008, Richier et al., 2008, Sekine et al., 2008, Shaik et al., 2008, Smith et al., 2008, Tanoue et al., 2008, Taylor and Hardin, 2008, T et al., 2008, Tomaiuolo et al., 2008, Wang et al., 2008, Yang et al., 2008, Yoshii et al., 2008, Zheng et al., 2008, Boothroyd et al., 2007, Busza et al., 2007, Codd et al., 2007, Dolezelova et al., 2007, Fang et al., 2007, Fang et al., 2007, Fujii et al., 2007, Gunawan and Doyle, 2007, Hart and Warrick, 2007, Helfrich-Forster et al., 2007, Hung et al., 2007, Kadener et al., 2007, Keegan et al., 2007, Ko et al., 2007, Konopka et al., 2007, Krupp et al., 2007, Kuczenski et al., 2007, Kurata et al., 2007, Lim et al., 2007, Lim et al., 2007, Matsumoto et al., 2007, Mehnert et al., 2007, Murad et al., 2007, Muskus et al., 2007, Nawathean et al., 2007, Picot et al., 2007, Stoleru et al., 2007, Suh and Jackson, 2007, Vosshall, 2007, Wijnen et al., 2007, Yoshii et al., 2007, Zheng et al., 2007, Akashi et al., 2006, Bartolome and Charlesworth, 2006, Chen et al., 2006, Dierick and Greenspan, 2006, Dunlap, 2006, Kadener et al., 2006, Kashi and King, 2006, Ko et al., 2006, Koh et al., 2006, Koh et al., 2006, Merrow, 2006, Morozova et al., 2006, Reppert, 2006, Rush et al., 2006, Sawyer et al., 2006, Shafer et al., 2006, Van Gelder, 2006, Wheeler et al., 2006, Wijnen et al., 2006, Yu and Hardin, 2006, Choi et al., 2005, Cyran et al., 2005, Gleason, 2005, Lear et al., 2005, Lear et al., 2005, Lin et al., 2005, Mazzoni et al., 2005, Paranjpe et al., 2005, Yoshii et al., 2005, Zhou et al., 2005, Geiger-Thornsberry and Mackay, 2004, Jaramillo et al., 2004, Klarsfeld et al., 2004, Majercak et al., 2004, Preuss et al., 2004, Rogers et al., 2004, Smolen et al., 2004, Yoshii et al., 2004, Beaver et al., 2003, Hall, 2003, Hendricks et al., 2003, Noor and Kliman, 2003, Powell et al., 2003, Hall, 2002, Levine et al., 2002, Levine et al., 2002, Shigeyoshi et al., 2002, Stanewsky et al., 2002, Yoshii et al., 2002, Blanchardon et al., 2001, Hendricks et al., 2001, Ivanchenko et al., 2001, Leloup and Goldbeter, 2001, Megighian et al., 2001, Petri and Stengl, 2001, Darlington et al., 2000, Driver, 2000, Kaneko et al., 2000, Lyons et al., 2000, Wright, 1987)
                                                                      Name Synonyms
                                                                      Clock
                                                                      clock-6
                                                                      period
                                                                      (Bilder, 2017, Li et al., 2017, Roessingh and Stanewsky, 2017, Tomita et al., 2017, Allen et al., 2016, Chen and Rosbash, 2016, Di Cara and King-Jones, 2016, Fu et al., 2016, Liao et al., 2016, Narayanan and Rothenfluh, 2016, Nikhil et al., 2016, Ou et al., 2016, Parisky et al., 2016, Anholt and Mackay, 2015, Cao and Edery, 2015, Chen et al., 2015, Donelson and Sanyal, 2015, Head et al., 2015, Jaumouillé et al., 2015, Lin et al., 2015, Merbitz-Zahradnik and Wolf, 2015, Nieto et al., 2015, Barclay et al., 2014, Goda et al., 2014, Long et al., 2014, Shi et al., 2014, Vrailas-Mortimer et al., 2014, Zheng et al., 2014, Ahmad et al., 2013, Billeter and Levine, 2013, Costa and Stanewsky, 2013, Garbe et al., 2013, Krupp et al., 2013, Lee et al., 2013, Rakshit et al., 2013, Yamamoto and Ishikawa, 2013, Bywalez et al., 2012, De et al., 2012, Ishimoto et al., 2012, Kaneko et al., 2012, Krishnan et al., 2012, Luo et al., 2012, Rakshit et al., 2012, Sakai et al., 2012, Gatto and Broadie, 2011, Griffith, 2011, Hara et al., 2011, Lamaze et al., 2011, Lone and Sharma, 2011, Lone et al., 2011, Mehnert and Cantera, 2011, Oliveira et al., 2011, Saez et al., 2011, Syed et al., 2011, Barth et al., 2010, Blanchard et al., 2010, Kuo et al., 2010, Li et al., 2010, Menet et al., 2010, Pereanu et al., 2010, Ruiz et al., 2010, Akten et al., 2009, Donlea et al., 2009, Fan et al., 2009, Górska-Andrzejak et al., 2009, Kilman et al., 2009, Krishnan et al., 2009, Landskron et al., 2009, Larsen et al., 2009, Lyons and Roman, 2009, Picot et al., 2009, Rieger et al., 2009, Sehadova et al., 2009, Weber et al., 2009, Yoshii et al., 2009, Yu et al., 2009, Zheng et al., 2009, Bagheri et al., 2008, Dunlap, 2008, Houl et al., 2008, Ito et al., 2008, Kadener et al., 2008, Kaiser and Cobb, 2008, Krishnan et al., 2008, Krupp et al., 2008, Lee and Edery, 2008, Lu et al., 2008, Sherazee et al., 2008, T et al., 2008, Tomaiuolo et al., 2008, Turner et al., 2008, Yoshii et al., 2008, Boothroyd et al., 2007, Busza et al., 2007, Dolezelova et al., 2007, Fang et al., 2007, Konopka et al., 2007, Krupp et al., 2007, Laayouni et al., 2007, Lim et al., 2007, Lim et al., 2007, Mehnert et al., 2007, Nawathean et al., 2007, Vosshall, 2007, Wijnen et al., 2007, Wu and Silverman, 2007, Korol et al., 2006, Morozova et al., 2006, Pereanu and Hartenstein, 2006, Reaume and Sokolowski, 2006, Sawyer et al., 2006, Van Gelder, 2006, Wheeler et al., 2006, Yu and Hardin, 2006, Cirelli et al., 2005, Cyran et al., 2005, Gleason, 2005, Lear et al., 2005, Mazzoni et al., 2005, Nitabach et al., 2005, Paranjpe et al., 2005, Zhou et al., 2005, Geiger-Thornsberry and Mackay, 2004, Jaramillo et al., 2004, Majercak et al., 2004, Preuss et al., 2004, Rogers et al., 2004, Beaver et al., 2003, Hall, 2003, Hendricks et al., 2003, Hall, 2002, Levine et al., 2002, Levine et al., 2002, Shigeyoshi et al., 2002, Stanewsky et al., 2002, Blanchardon et al., 2001, Ivanchenko et al., 2001, Leloup and Goldbeter, 2001, Megighian et al., 2001, Petri and Stengl, 2001, Darlington et al., 2000, Driver, 2000, Kaneko et al., 2000, Lyons et al., 2000, Kliman, 1993.2.25, Kliman, 1993.2.25, Kliman, 1993.2.25, Kliman, 1993.2.25, Kliman, 1993.2.25, Kliman, 1993.2.25, Wright, 1987)
                                                                      period clock protein
                                                                      Secondary FlyBase IDs
                                                                      • FBgn0000321
                                                                      • FBgn0020918
                                                                      Datasets (0)
                                                                      Study focus (0)
                                                                      Experimental Role
                                                                      Project
                                                                      Project Type
                                                                      Title
                                                                      References (1,235)