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General Information
Symbol
Dmel\Pc
Species
D. melanogaster
Name
Polycomb
Annotation Symbol
CG32443
Feature Type
FlyBase ID
FBgn0003042
Gene Model Status
Stock Availability
Gene Snapshot
Polycomb (Pc) encodes a chromatin binding protein that interacts with histone H3K27me3. It is involved in epigenetic silencing and its target genes are predominantly transcription factors or receptors that control cell fate and most developmental decisions. [Date last reviewed: 2019-03-14]
Also Known As
PcG, Pc-G
Key Links
Genomic Location
Cytogenetic map
Sequence location
3L:21,306,138..21,318,020 [-]
Recombination map
3-47
Sequence
Other Genome Views
The following external sites may use different assemblies or annotations than FlyBase.
Function
GO Summary Ribbons
Protein Family (UniProt)
-
Summaries
Gene Group (FlyBase)
POLYCOMB REPRESSIVE COMPLEX 1 (CORE SUBUNITS) -
The Polycomb repressive complex 1 (PRC1) is a Polycomb group complex. It binds to histone H3K27me3 (histone H3 K27 methylation is catalyzed by PRC2) and monoubiquitinates H2A on K119. This leads to chromatin compaction, RNA polymerase II stalling and gene silencing. (Adapted from FBrf0179742 and FBrf0228921).
Protein Function (UniProtKB)
Polycomb group (PcG) protein. PcG proteins act by forming multiprotein complexes, which are required to maintain the transcriptionally repressive state of homeotic genes throughout development. PcG proteins are not required to initiate repression, but to maintain it during later stages of development. Component of the PcG multiprotein PRC1 complex, a complex that acts via chromatin remodeling and modification of histones; it mediates monoubiquitination of histone H2A 'Lys-118', rendering chromatin heritably changed in its expressibility. Promotes locus-specific chromatin compaction.
(UniProt, P26017)
Phenotypic Description (Red Book; Lindsley and Zimm 1992)
Pc: Polycomb
Pc+ may be considered a negative regulator of the bithorax complex (BXC) and the Antennapedia complex (ANTC), with a decreasing gradient of activity from anterior to posterior. When homozygous or hemizygous, Pc mutants are late embryonic lethals. Embryos with at least one dose of the BXC show incomplete head development and caudad transformations, the thoracic and first seven abdominal segments being partially transformed into the eighth abdominal segment (Lewis, 1978; Denell, 1982; Haynie, 1983, Dev. Biol. 100: 399-411; Denell and Frederick, 1983, Dev. Biol. 97: 34-47). This homeotic effect in homozygotes is enhanced by increasing the dosage of the BXC. Transformations involve brain and ventral nerve cord as well as epidermis (Jimenez and Campos-Ortega, 1981). Pc+ alleles in the mother weaken the homeotic effect (Denell, 1982; Lawrence, Johnson, and Struhl, 1983, Cell 35: 27-34). Pc2/Pc2 or Pc3/Pc3 clones induced in leg and eye-antennal tissue during larval development also show similar posteriorly-directed transformations (Struhl, 1981; Duncan and Lewis, 1982). Pc/+ flies carrying at least one dose of the BXC show caudad transformations, i.e. partial conversion of wings into halteres and of anterior abdominal segments into more posterior ones. Some Pc heterozygotes show phenotypes characteristic of ANTC mutants, i.e. partial conversion of antennae into legs and of second and third legs into first legs (with sex combs in males) (Hannah-Alava, 1958; Duncan, 1982). The frequency of wing transformations varies directly with the BXC dosage, but does not seem to be changed by variation in ANTC dosage (Duncan and Lewis, 1982; Botas et al., 1982). The number of abdominal transformations, however, varies inversely with the doses of the BXC while it increases as the doses of the ANTC are increased (Duncan, 1982; Duncan and Lewis, 1982). Other changes observed in Pc/+ flies include a transformation of ventral to dorsal wing (Tiong; Sato et al., 1983), elevated, divergent, or crinkled wings, terminal gaps in the L4 wing vein, bent humeral or notopleural bristles, and defective sternopleural bristles, all abnormalities being less extreme in males than in females (sometimes absent in males). When doubly heterozygous with AntpYu and AntpB, Pc enhances Antp. The expression of all Pc mutant heterozygotes (including deficiencies for the locus) is enhanced by the second chromosome dominant, E(Pc) (Sato et al., 1983, 1984). Pc3/Pc3/Dp(1;3;4)7 flies (carrying a Pc+ duplication) show stronger leg and wing transformations than E(Pc)/+;Pc3/+ flies (Duncan and Lewis, 1982; Sato et al., 1983).
Summary (Interactive Fly)
transcription factor - chromo domain - Polycomb group - chromatin associated protein - involved in gene silencing chromatin binding protein that interacts with histone H3K27me3 - Pc target genes are predominantly transcription factors or receptors that control cell fate and most developmental decisions
Gene Model and Products
Number of Transcripts
1
Number of Unique Polypeptides
1

Please see the GBrowse view of Dmel\Pc or the JBrowse view of Dmel\Pc 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)
FBtr0078405
2462
390
Additional Transcript Data and Comments
Reported size (kB)
2.5, 2.0 (northern blot)
Comments
External Data
Crossreferences
Polypeptide Data
Annotated Polypeptides
Name
FlyBase ID
Predicted MW (kDa)
Length (aa)
Theoretical pI
RefSeq ID
GenBank
FBpp0078059
44.0
390
7.64
Polypeptides with Identical Sequences

There is only one protein coding transcript and one polypeptide associated with this gene

Additional Polypeptide Data and Comments
Reported size (kDa)
390 (aa); 44 (kD predicted)
Comments
A variation on the in vivo formaldehyde cross-linking technique was used to map Pc-interacting sites along the chromatin in the BX-C region. Pc was found to quantitatively cover large regulatory regions of repressed BX-C genes. Pc did not bind the transcriptionally active Abd-B region.
Pc protein and polyhomeotic protein are coprecipitated by antibodies to either showing that they are constituents of a multimeric protein complex. Pc and polyhomeotic complexes can be coprecipitated over the entire period of embryogenesis. The molecular weight of the complex is ~2-5x103kD. Double-immunofluorescence labeling was used to show that Pc protein and polyhomeotic protein have exactly the same binding patterns on polytene chromosomes.
Pc protein is associated with ~60 sites on the polytene chromosomes. It is associated with loci shown to interact with Pc by genetic methods. It is abundant at the ANT-C and the BX-C and is found at several locations of Pc-group genes. The Pc protein expressed in salivary glands is encoded by a 1.0kb Pc transcript and is smaller than the 390aa Pc protein.
External Data
Subunit Structure (UniProtKB)
Component of PRC1 complex, which contains many PcG proteins like Pc, ph, Scm, Psc, Sce and also chromatin-remodeling proteins such as histone deacetylases. This complex is distinct from the Esc/E(z) complex, at least composed of esc, E(z), Su(z)12, Rpd3 and Caf1. The 2 complexes however cooperate and interact together during the first 3 hours of development to establish PcG silencing (PubMed:11493925, PubMed:11583617). Interacts with stx; the interaction targets Pc for ubiquitin-independent proteasomal degradation (PubMed:27326929).
(UniProt, P26017)
Linkouts
Sequences Consistent with the Gene Model
Mapped Features

Click to get a list of regulatory features (enhancers, TFBS, etc.) and gene disruptions (point mutations, indels, etc.) within or overlapping Dmel\Pc 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 (21 terms)
Molecular Function (4 terms)
Terms Based on Experimental Evidence (4 terms)
CV Term
Evidence
References
Terms Based on Predictions or Assertions (1 term)
CV Term
Evidence
References
Biological Process (11 terms)
Terms Based on Experimental Evidence (11 terms)
CV Term
Evidence
References
inferred from mutant phenotype
inferred from genetic interaction with FLYBASE:ph-p; FB:FBgn0004861
inferred from mutant phenotype
inferred from mutant phenotype
inferred from high throughput mutant phenotype
inferred from mutant phenotype
Terms Based on Predictions or Assertions (0 terms)
Cellular Component (6 terms)
Terms Based on Experimental Evidence (5 terms)
CV Term
Evidence
References
inferred from direct assay
inferred from direct assay
inferred from direct assay
Terms Based on Predictions or Assertions (2 terms)
CV Term
Evidence
References
Expression Data
Expression Summary Ribbons
Colored tiles in ribbon indicate that expression data has been curated by FlyBase for that anatomical location. Colorless tiles indicate that there is no curated data for that location.
For complete stage-specific expression data, view the modENCODE Development RNA-Seq section under High-Throughput Expression below.
Transcript Expression
No Assay Recorded
Stage
Tissue/Position (including subcellular localization)
Reference
in situ
Stage
Tissue/Position (including subcellular localization)
Reference
organism | ubiquitous

Comment: maternally deposited

northern blot
Stage
Tissue/Position (including subcellular localization)
Reference

Comment: reference states 0-8 hr AEL

Additional Descriptive Data
Marker for
 
Subcellular Localization
CV Term
Polypeptide Expression
immunolocalization
Stage
Tissue/Position (including subcellular localization)
Reference
Additional Descriptive Data
The Pc protein accumulates in the region of the bithorax complex genes on polytene chromosomes from anterior regions of larval fat bodies where the homeotic genes are repressed.
The distribution of polyhomeotic protein and Pc protein is nearly indistinguishable in embryos.
Pc protein is expressed in ovaries and during all stages of embryogenesis. Protein levels increase with developmental time in embryos. Two phases of Pc expression are observed in ovaries. First, substantial Pc protein is found in the germarium and in stage S1 and S2 follicles. Protein levels decline during stages S3-S8 and rise again in stages S9 and S10. In the germline, most of the protein is found in the polyploid nurse cell nuclei. Some Pc protein is deposited in the oocyte but none is observed in the nucleus. A very dynamic pattern of expression involving overlapping gradients is observed in follicle cells during stages S10-S14. In embryos, Pc transcripts are homogenously distributed over the length of the embryo at the cellular blastoderm stage and in germ band extended embryos. In late stage embryos, transcripts are found predominantly in the CNS. Particularly strong expression is observed in the supra-, suboesophageal and anterior thoracic ganglia. Strong staining is also observed in the pharynx, salivary glands, and other internal tissues.
Marker for
 
Subcellular Localization
CV Term
Evidence
References
inferred from direct assay
inferred from direct assay
inferred from direct assay
Expression Deduced from Reporters
High-Throughput Expression Data
Associated Tools

GBrowse - Visual display of RNA-Seq signals

View Dmel\Pc 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
BDGP expression data - Patterns of gene expression in Drosophila embryogenesis
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, and Transgenic Constructs
Phenotypes
For more details about a specific phenotype click on the relevant allele symbol.
Lethality
Allele
Other Phenotypes
Allele
Phenotype manifest in
Allele
dendrite & dorsal multidendritic neuron ddaC | somatic clone
mesothoracic leg & sex comb | ectopic
mesothoracic leg & sex comb tooth | ectopic
metathoracic leg & sex comb | ectopic
metathoracic leg & sex comb tooth | ectopic
Orthologs
Human Orthologs (via DIOPT v7.1)
Homo sapiens (Human) (5)
Species\Gene Symbol
Score
Best Score
Best Reverse Score
Alignment
Complementation?
Transgene?
8 of 15
Yes
Yes
8 of 15
Yes
Yes
6 of 15
No
Yes
5 of 15
No
Yes
5 of 15
No
Yes
Model Organism Orthologs (via DIOPT v7.1)
Mus musculus (laboratory mouse) (6)
Species\Gene Symbol
Score
Best Score
Best Reverse Score
Alignment
Complementation?
Transgene?
8 of 15
Yes
Yes
7 of 15
No
Yes
6 of 15
No
Yes
6 of 15
No
Yes
3 of 15
No
Yes
 
 
3 of 15
No
Yes
Rattus norvegicus (Norway rat) (5)
5 of 13
Yes
Yes
4 of 13
No
Yes
3 of 13
No
Yes
3 of 13
No
Yes
3 of 13
No
Yes
Xenopus tropicalis (Western clawed frog) (5)
6 of 12
Yes
Yes
5 of 12
No
Yes
3 of 12
No
Yes
3 of 12
No
Yes
3 of 12
No
Yes
Danio rerio (Zebrafish) (9)
7 of 15
Yes
Yes
7 of 15
Yes
Yes
5 of 15
No
Yes
4 of 15
No
Yes
4 of 15
No
Yes
4 of 15
No
Yes
3 of 15
No
Yes
2 of 15
No
Yes
1 of 15
No
Yes
Caenorhabditis elegans (Nematode, roundworm) (1)
3 of 15
Yes
Yes
Arabidopsis thaliana (thale-cress) (0)
No records found.
Saccharomyces cerevisiae (Brewer's yeast) (0)
No records found.
Schizosaccharomyces pombe (Fission yeast) (0)
No records found.
Orthologs in Drosophila Species (via OrthoDB v9.1) ( EOG09190DG5 )
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 yakuba
Drosophila yakuba
Drosophila ananassae
Drosophila pseudoobscura pseudoobscura
Drosophila persimilis
Drosophila willistoni
Drosophila virilis
Drosophila mojavensis
Drosophila grimshawi
Orthologs in non-Drosophila Dipterans (via OrthoDB v9.1) ( EOG09150CWN )
Organism
Common Name
Gene
Multiple Dmel Genes in this Orthologous Group
Musca domestica
House fly
Glossina morsitans
Tsetse fly
Aedes aegypti
Yellow fever mosquito
Anopheles darlingi
American malaria mosquito
Culex quinquefasciatus
Southern house mosquito
Orthologs in non-Dipteran Insects (via OrthoDB v9.1) ( EOG090W0ESN )
Organism
Common Name
Gene
Multiple Dmel Genes in this Orthologous Group
Bombyx mori
Silkmoth
Danaus plexippus
Monarch butterfly
Heliconius melpomene
Postman butterfly
Apis florea
Little honeybee
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
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) ( EOG090X0ES0 )
Organism
Common Name
Gene
Multiple Dmel Genes in this Orthologous Group
Strigamia maritima
European centipede
Strigamia maritima
European centipede
Ixodes scapularis
Black-legged tick
Stegodyphus mimosarum
African social velvet spider
Stegodyphus mimosarum
African social velvet spider
Tetranychus urticae
Two-spotted spider mite
Tetranychus urticae
Two-spotted spider mite
Daphnia pulex
Water flea
Orthologs in non-Arthropod Metazoa (via OrthoDB v9.1) ( EOG091G0NOT )
Organism
Common Name
Gene
Multiple Dmel Genes in this Orthologous Group
Strongylocentrotus purpuratus
Purple sea urchin
Paralogs
Paralogs (via DIOPT v7.1)
Drosophila melanogaster (Fruit fly) (0)
No records found.
Human Disease Associations
FlyBase Human Disease Model Reports
Disease Model Summary Ribbon
Disease Ontology (DO) Annotations
Models Based on Experimental Evidence ( 0 )
Allele
Disease
Evidence
References
Potential Models Based on Orthology ( 1 )
Human Ortholog
Disease
Evidence
References
Modifiers Based on Experimental Evidence ( 0 )
Allele
Disease
Interaction
References
Comments on Models/Modifiers Based on Experimental Evidence ( 0 )
 
Disease Associations of Human Orthologs (via DIOPT v7.1 and OMIM)
Note that ortholog calls supported by only 1 or 2 algorithms (DIOPT score < 3) are not shown.
Homo sapiens (Human)
Gene name
Score
OMIM
OMIM Phenotype
DO term
Complementation?
Transgene?
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 see the Physical Interaction reports below for full details
protein-protein
Physical Interaction
Assay
References
RNA-protein
Physical Interaction
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
suppressible
suppressible
External Data
Subunit Structure (UniProtKB)
Component of PRC1 complex, which contains many PcG proteins like Pc, ph, Scm, Psc, Sce and also chromatin-remodeling proteins such as histone deacetylases. This complex is distinct from the Esc/E(z) complex, at least composed of esc, E(z), Su(z)12, Rpd3 and Caf1. The 2 complexes however cooperate and interact together during the first 3 hours of development to establish PcG silencing (PubMed:11493925, PubMed:11583617). Interacts with stx; the interaction targets Pc for ubiquitin-independent proteasomal degradation (PubMed:27326929).
(UniProt, P26017 )
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.
MIST (genetic) - An integrated Molecular Interaction Database
MIST (protein-protein) - An integrated Molecular Interaction Database
Pathways
Genomic Location and Detailed Mapping Data
Chromosome (arm)
3L
Recombination map
3-47
Cytogenetic map
Sequence location
3L:21,306,138..21,318,020 [-]
FlyBase Computed Cytological Location
Cytogenetic map
Evidence for location
78C6-78C7
Limits computationally determined from genome sequence between P{lacW}l(3)j1B10j1B10 and P{lacW}l(3)j2C4j2C4
Experimentally Determined Cytological Location
Cytogenetic map
Notes
References
78D7-78D8
(determined by in situ hybridisation)
Location from complementation analysis with deficiency and duplication chromosomes (details unspecified).
Experimentally Determined Recombination Data
Right of (cM)
Notes
Stocks and Reagents
Stocks (37)
Genomic Clones (13)
 

Please Note FlyBase no longer curates genomic clone accessions so this list may not be complete

cDNA Clones (163)
 

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
Linkouts
DRSC - Results frm RNAi screens
GenomeRNAi - A database for cell-based and in vivo RNAi phenotypes and reagents
Antibody Information
Laboratory Generated Antibodies
Commercially Available Antibodies
 
Other Information
Relationship to Other Genes
Source for database identify of
Source for database merge of
Additional comments
Other Comments
Haploinsufficient locus (not associated with strong haplolethality or haplosterility).
DNA-protein interactions: genome-wide binding profile assayed for Pc protein in Kc167 cells; see Chromatin_types_NKI collection report. Individual protein-binding experiments listed under "Samples" at GEO_GSE22069 (http://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE22069).
Pc is required for normal neuroblast survival and proliferation in postembryonic central nervous system development.
Pc is required for for the maintenance of dendritic fields in class IV dendrite arborisation (da) neurons.
dsRNA made from templates generated with primers directed against Pc used to treat S2 cells results in a decreased proportion of cells in G1 and S phase, with an accompanying increase in G2/M cells. This modification of the cell cycle profile occurs in the absence of any apparent growth defect.
Mutant allele fails to complement a QTL affecting male mating behaviour.
Pc-G proteins can silence gene expression at a large number of chromosomal locations, affecting both enhancer-activated and basal w transcription. Repression is observed even with separation distances of up to 3.0kb between target promoters and binding sites for tethered Pc-G proteins.
Mutant analysis demonstrates functional interactions between Pc, sxc and Asx in vivo.
Pc protein is associated with genes silenced as part of the cosuppression phenomenon.
Pc, Scm, Psc, ph-p and ph-d contribute to the PRC1 (Polycomb repressive complex 1). PRC1 directly antagonizes ATP-dependent remodeling of nucleosomal arrays in a purified system and may directly modulate (and be modified by) SWI/SNF (brm/mor) activity.
Evidence of physical interaction between esc and E(z) in vitro and in vivo and coimmunoprecipitation in vivo suggests the proteins are direct partners in Pc-G mediated repression and this relationship has been evolutionarily conserved.
ph-p, Psc and Pc proteins coimmunoprecipitate from nuclear extracts. Interacting domains are identified and delimited using the two-hybrid system, the interactions are shown to be direct by using an in vitro binding assay.
The Pc and trx gene products bind to PRE target sequences by cellular blastoderm, when the bithorax complex transcription begins. At the same stage trx but not Pc gene product is strongly associated with core promoters. At germ band extension, the time of derepression in Pc mutants, Pc gene product is found outside core PREs.
Abd-B MCP725 element is a silencer that functions throughout proliferation of the imaginal discs. MCP725-mediated silencing requires the Pc and Pcl proteins (it is likely that other members of the PcG also interact with the MCP725 silencer).
Mutant phenotype suppressed by alleles of kis and (weakly) EcR.
Silencing activity of the iab-7PRE in the bithorax complex is dependent upon proteins from the Polycomb group.
The chromodomain of Pc is necessary for protein-protein interactions within a Pc-polyhomeotic complex. In addition, Psc protein coimmunoprecipitates Pc and polyhomeotic indicating they are members of a common multimeric protein complex. These three proteins are associated with identical regulatory elements of en in tissue culture cells and differentially distributed on regulatory sequences of inv.
The distribution of Pc protein on the bithorax complex of Drosophila tissue culture cells has been mapped. The protein is not distributed homogeneously on the regulatory regions of the repressed Ubx and abd-A genes, but is highly enriched at discrete sequence elements, many of which coincide with previously mapped Pc response elements (PREs). Trl protein is also bound at those PREs which contain Trl consensus-binding sites.
Using reporter gene constructs the Pc group response elements (PRE) behaves as an orientation-dependent silencer capable of inducing mosaic gene expression on neighbouring genes.
In an effort to subdivide the Pc-group genes functionally, the phenotypes of adult flies heterozygous for every pairwise combination of Pc-group mutation were examined. Asx, Pc, Pcl, Psc, Scm and Sce have similar functions in some imaginal tissues. Genetic interactions have been demonstrated between esc, Asx, E(Pc), Pcl, E(z) and sxc. Most duplications of Pc-group genes neither exhibit anterior transformations nor suppress the extra sex comb phenotype of Pc-group mutations, suggesting that not all Pc-group genes behave as predicted by the mass action model.
Proper regulation of both trx and Pc can be established by transient assays with a haploid cell line expressing Ubx promoters fused to a Ecol\lacZ reporter gene. This system has been used to map the regulatory sequences in the Ubx promoter to a 440bp region. The Ubx proximal promoter is essential for trx-dependent activation.
Pc associates with multiple sites in the bithorax complex and these sites all contain maintenance elements, as defined by a Ecol\lacZ expression assay.
The negative autoregulation of ph-p starts at the blastoderm stage and is partly mediated by a transvection effect. As the number of functional copies of ph-p increases a concomitant reduction of the transcription in each copy is observed. This regulation is ensured positively by the trx group and negatively by the Pc group gene products.
Sections of the Scr regulatory region may be important for regulation of Scr by Polycomb- and trithorax-group genes.
Mutations of Pc interact with Dfd to reduce the viability of the Dfd3/Dfd13 combination.
A Pc-response element has been identified in an intron of abd-A.
Phenotypic rescue of Pc- larvae cuticle phenotype and Pc- clones of adult cells demonstrates the Mmus\Cbx2 protein can emulate Pc both early and late in development.
Pc acts as a transcriptional silencer in embryos if tethered to reporter genes by the DNA binding domain of Scer\GAL4 (as a Scer\GAL4-Pc fusion gene). Silencing by Scer\GAL4-Pc requires the C-terminal portion, but not the chromodomain.
A method based on in-vivo formaldehyde crosslinking and chromatin immunoprecipitation has allowed the determination of the in vivo distribution of Pc, brm and Abd-B products at their target sites.
A chimeric Su(var)205-Pc protein (the chromo domain of Pc in the context of Su(var)205) causes mislocalisation of Su(var)205 to Pc binding sites and expression in transgenic flies promotes heterochromatin mediated gene silencing. Results support the view that the chromo domain homology reflects a common mechanistic basis for homeotic and heterochromatic silencing.
The ventral to dorsal effect of Pc mutants is mediated through Dlw.
Pc group response elements found in the Fab and Mcp regions of Abd-B induce mosaic expression of w+mC, this is dependent on Pc.
Members of the Pc group function as potent repressors in mammalian cells.
Duplication of ph-d suppress homeotic transformations of Pc and Pcl, this data supports the conclusion that ph-d is at equilibrium with a multimeric complex containing Pc group genes.
Pc product is found on larval salivary chromosomes at about 100 specific loci, in the same positions as the products of Pcl, ph-d and ph-p genes.
Mutation analysis and en expression patterns demonstrate a role for Pc gene in regulation of some segmentation genes.
P elements bearing ph-p regulatory sequences preferentially insert into regions containing known Pc and ph-p protein binding sites, perhaps because shared regulatory proteins bring transposons and insertion sites into close proximity.
Pc binds polytene chromosomes at 45 locations where other Pc-group proteins, encoded by the Psc and polyhomeotic genes, are present.
Distribution of the Pc protein in the bithorax complex was determined, and Pc protein quantitatively covers large regulatory regions of repressed genes.
There is considerable overlap of chromosomal binding sites for Psc, Su(z)2, z, Pc and the polyhomeotic proteins.
The bithorax complex genes are regulated by the Pc group of genes, acting via 'Pc group response elements' (PREs), that can work even when removed from the normal bithorax complex context. The Pc group products apparently provide stable memory or imprinting of boundaries which are specified by gap and pair-rule regulators.
Extensive overlap exists between the binding sites of ph-p and Pc on polytene chromosomes.
Pc and polyhomeotic proteins are constituents of a soluble multimeric nuclear protein complex.
When homozygous or hemizygous, Pc mutants are late embryonic lethals. Embryos with at least one dose of the BXC show incomplete head development and caudal transformations, the thoracic and first seven abdominal segments being partially transformed into the eighth abdominal segment (FBrf0032262; FBrf0063402; FBrf0039217; FBrf0039211). This homeotic effect in homozygotes is enhanced by increasing the dosage of the BXC. Transformations involve brain and ventral nerve cord as well as epidermis (FBrf0037316). Pc+ alleles in the mother weaken the homeotic effect (FBrf0063402; FBrf0038997). Pc2/Pc2 or Pc3/Pc3 clones induced in leg and eye-antennal tissue during larval development also show similar posteriorly-directed transformations (FBrf0037148; FBrf0063405). Pc/+ flies carrying at least one dose of the BXC show caudal transformations, i.e. partial conversion of wings into halteres and of anterior abdominal segments into more posterior ones. Some Pc heterozygotes show phenotypes characteristic of ANTC mutants, i.e. partial conversion of antennae into legs and of second and third legs into first legs (with sex combs in males) (FBrf0012037; FBrf0038059). The frequency of wing transformations varies directly with the BXC dosage, but does not seem to be changed by variation in ANTC dosage (FBrf0063405; FBrf0037909). The number of abdominal transformations, however, varies inversely with the doses of the BXC while it increases as the doses of the ANTC are increased (FBrf0038059; FBrf0063405). Other changes observed in Pc/+ flies include a transformation of ventral to dorsal wing (FBrf0051513; FBrf0039451), elevated, divergent, or crinkled wings, terminal gaps in the L4 wing vein, bent humeral or notopleural bristles, and defective sternopleural bristles, all abnormalities being less extreme in males than in females (sometimes absent in males). When doubly heterozygous with AntpYu and AntpB, Pc enhances Antp. The expression of all Pc mutant heterozygotes (including deficiencies for the locus) is enhanced by the second chromosome dominant, E(Pc) (FBrf0039451; FBrf0040741). Pc3/Pc3/Dp(1;3;4)7 flies (carrying a Pc+ duplication) show stronger leg and wing transformations than E(Pc)/+; Pc3/+ flies (FBrf0063405; FBrf0039451).
Pc+ may be considered a negative regulator of the bithorax complex (BXC) and the Antennapedia complex (ANTC), with a decreasing gradient of activity from anterior to posterior.
The chromo domain is a homologous protein motif between Pc and Su(var)205. Transgenic lines and transient assays in culture cells have been used to determine the functional role of the Pc chromo domain, it is important for the function of Pc and is absolutely required for binding of Pc protein to chromatin. The chromo domain could be involved in a packaging mechanism essential for compacting chromosomal proteins within heterochromatin or heterochromatin-like complexes.
Embryos mutant for two or more Pc group genes (Pc, Scm, Pcl, Psc, Asx, E(Pc), E(z), ph-d, pho and esc) show strong ectopic en expression, but only weak derepression occurs if embryo is mutant at only one of the Pc group genes. This effect is independent of the function of en itself, and wg.
Developmental profile of Pc gene products demonstrates that Pc is down-regulated by one of its own targets, Ubx.
Mutations of genes in the polycomb group (esc, E(z), Pc, ph-p, ph-d, Scm, Pcl, Sce, Asx, Psc, pho and Antp) cause abnormal segmental development due to the ectopic expression of abd-A and Abd-B. Embryos lacking both maternal and zygotic Pc product were generated to determine abd-A and Abd-B expression patterns.
Pc dominant loss-of-function mutants cause widespread alterations in cell fates by derepressing genes in the BXC and ANTC.
The Pc group genes are negative regulators of homeotic genes.
Mutations in maternal class gene Pc do not interact with RpII140wimp.
Pc has been cloned and sequenced.
Homeotic gene activity programs primordia as either discs or histoblast nests by the early extended germ band stage. In Pc- embryos homeotic gene expression is no longer restricted to the normal expression domains.
The Pc gene product regulates Antp transcription directly at the chromosomal level. Regulation of Antp P2 differs from Antp P1 in that in that it can be repressed by transacting factors other than Pc.
The role of Pc in maintaining stable patterns of homeotic gene transcription has been studied.
Interactions with a mutation of the Pc gene were used to confirm that ash1 and ash2 are members of a functionally related class of genes whose alleles have similar transformation properties to mutations of trx. The dominant extra sex combs phenotype of adult males heterozygous for Pc mutations is sensitive to the gene dosage of trx, and is suppressed by heterozygosity for a trx deletion and enhanced by heterozygosity for a trx duplication.
Cell clones deficient for Pc and the BXC genes have abnormal wings and legs, Scr and en are derepressed in the absence of Pc and BXC function. By using the Pc- mutation and various BXC mutant combinations imaginal cell clones possessing different combinations of active homeotic genes have been generated. In the absence of BXC genes Pc- clones develop prothoracic patterns: Scr activity overrules Antp. Adding contributions of Ubx, abd-A and Abd-B results in thoracic or abdominal patterns.
Mutations in 18 complementation groups identify modifiers of Pc and/or Antp phenotypes. All 18 complementation groups are required for viability. Alleles of Pc, Pcl, Scm, Dll, brm, kto, Scr and trx show clear dominant enhancement or suppression of AntpScx, whereas alleles of vtd, Vha55, Su(Pc)37D, urd, mor, skd and osa do not.
Mutants of Pc exhibit a reduction in sex comb teeth on the second and third legs.
Genetic analysis of the Pc locus suggests it is a complex gene. Insufficiency of Pc products can be corrected by insufficiency of hb products or be exaggerated by the excess of the same products. Pc+ products regulate the expression Of the Ubx protein coding region.
The effect of various mutations in the bithorax and antennapedia complexes on the Pc mutant phenotype has been studied.
Pc mutants display homeotic transformation of head and thoracic segments towards A8.
Mutant males display sex combs in the second and third legs.
Origin and Etymology
Discoverer
Etymology
Identification
External Crossreferences and Linkouts ( 55 )
Sequence 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.
GenBank Nucleotide - A collection of sequences from several sources, including GenBank, RefSeq, TPA, and PDB.
GenBank Protein - A collection of sequences from several sources, including translations from annotated coding regions in GenBank, RefSeq and TPA, as well as records from SwissProt, PIR, PRF, and PDB.
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
BDGP expression data - Patterns of gene expression in Drosophila embryogenesis
Drosophila Genomics Resource Center - Drosophila Genomics Resource Center (DGRC) cDNA clones
Eukaryotic Promoter Database - A collection of databases of experimentally validated promoters for selected model organisms.
Fly-FISH - A database of Drosophila embryo and larvae mRNA localization patterns
Flygut - An atlas of the Drosophila adult midgut
GenomeRNAi - A database for cell-based and in vivo RNAi phenotypes and reagents
iBeetle-Base - RNAi phenotypes in the red flour beetle (Tribolium castaneum)
KEGG Genes - Molecular building blocks of life in the genomic space.
modMine - A data warehouse for the modENCODE project
SignaLink - A signaling pathway resource with multi-layered regulatory networks.
Linkouts
BioGRID - A database of protein and genetic interactions.
DPiM - Drosophila Protein interaction map
DroID - A comprehensive database of gene and protein interactions.
DRSC - Results frm RNAi screens
FLIGHT - Cell culture data for RNAi and other high-throughput technologies
FlyAtlas - Adult expression by tissue, using Affymetrix Dros2 array
FlyMine - An integrated database for Drosophila genomics
Interactive Fly - A cyberspace guide to Drosophila development and metazoan evolution
InterologFinder - Protein-protein interactions (PPI) from both known and predicted PPI data sets.
MIST (genetic) - An integrated Molecular Interaction Database
MIST (protein-protein) - An integrated Molecular Interaction Database
Synonyms and Secondary IDs (12)
Reported As
Symbol Synonym
CG7618
Pc
(Gervais et al., 2019, Leatham-Jensen et al., 2019, Parey and Crombach, 2019, Pherson et al., 2019, Dasari et al., 2018, Davis and Rebay, 2018, La Fortezza et al., 2018, Lv et al., 2018, Nishioka et al., 2018, Rosales-Vega et al., 2018, Rybina et al., 2018, Sadasivam and Huang, 2018, Yao et al., 2018, Akishina et al., 2017, Dutta and Li, 2017, Eagen et al., 2017, Maini et al., 2017, Marshall and Brand, 2017, Monribot-Villanueva et al., 2017, Schwartz and Cavalli, 2017, Sharma et al., 2017, Transgenic RNAi Project members, 2017-, Aggarwal et al., 2016, Cruz-Becerra et al., 2016, Du et al., 2016, Frey et al., 2016, Harris et al., 2016, Kahn et al., 2016, Lv et al., 2016, Morata and Herrera, 2016, Morimoto et al., 2016, Peng et al., 2016, Piunti and Shilatifard, 2016, Ray et al., 2016, Shih et al., 2016, Shlyueva et al., 2016, Wani et al., 2016, Bivik et al., 2015, Dietz et al., 2015, Dupont et al., 2015, Erokhin et al., 2015, Finley et al., 2015, Grifoni et al., 2015, Hsu et al., 2015, Kang et al., 2015, Kim et al., 2015, Lee et al., 2015, Li et al., 2015, McKay et al., 2015, Ríos-Barrera et al., 2015, Saberi et al., 2015, Yung et al., 2015, Zang et al., 2015, Comoglio and Paro, 2014, Fereres et al., 2014, Gambetta and Müller, 2014, Gonzalez et al., 2014, Herrera and Morata, 2014, Liu et al., 2014, Maksimenko et al., 2014, McElroy et al., 2014, Ost et al., 2014, Pascual-Garcia et al., 2014, Stern et al., 2014, Tie et al., 2014, Aloia et al., 2013, Debruhl et al., 2013, Di Croce and Helin, 2013, Iovino et al., 2013, Lim et al., 2013, Mason-Suares et al., 2013, Mulero et al., 2013, Schaaf et al., 2013, Vaque et al., 2013, Vasanthi et al., 2013, Antao et al., 2012, Cheutin and Cavalli, 2012, Cook et al., 2012, Cuddapah et al., 2012, Gutiérrez et al., 2012, Hainaut et al., 2012, Herz et al., 2012, Ji et al., 2012, Langlais et al., 2012, Lim et al., 2012, Meier et al., 2012, Park et al., 2012, Petruk et al., 2012, Popkova et al., 2012, Pushpavalli et al., 2012, Rincon-Arano et al., 2012, Sakoparnig et al., 2012, Stern et al., 2012, Wen et al., 2012, Anderson et al., 2011, Bantignies et al., 2011, Cavalli, 2011, Chen et al., 2011, Choo et al., 2011, Davis et al., 2011, Enderle et al., 2011, Grau et al., 2011, Katsuyama and Paro, 2011, Mikhaylova and Nurminsky, 2011, Okulski et al., 2011, Pruteanu-Malinici et al., 2011, Rodriguez-Jato et al., 2011, Strübbe et al., 2011, Sultana et al., 2011, Ahn et al., 2010, Baig et al., 2010, Basu and Atchison, 2010, Bhatia et al., 2010, Brown and Kassis, 2010, Campos et al., 2010, Gan et al., 2010, Grau et al., 2010, Guertin and Lis, 2010, Herz et al., 2010, Huen and Russell, 2010, Lamiable et al., 2010, Lee et al., 2010, Li et al., 2010, modENCODE Consortium et al., 2010, Saj et al., 2010, Smulders-Srinivasan et al., 2010, Wang et al., 2010, Wilkinson et al., 2010, Classen et al., 2009, Fang et al., 2009, Francis et al., 2009, Gambetta et al., 2009, Gambetta et al., 2009, González and Busturia, 2009, Khan et al., 2009, Lo et al., 2009, Schaaf et al., 2009, Shevelyov et al., 2009, Sinclair et al., 2009, Sinclair et al., 2009, Sing et al., 2009, Tariq et al., 2009, Tie et al., 2009, Zhai et al., 2009, Chalkley et al., 2008, Chen et al., 2008, de Wit et al., 2008, Diop et al., 2008, Dixit et al., 2008, Doheny et al., 2008, Estella et al., 2008, Fedorova et al., 2008, Fujioka et al., 2008, Garaulet et al., 2008, González et al., 2008, Hallson et al., 2008, Hauenschild et al., 2008, Jung et al., 2008, Kwong et al., 2008, Lagarou et al., 2008, Lin et al., 2008, McDermott and Kliman, 2008, Pauli et al., 2008, Petruk et al., 2008, Pham et al., 2008, Zhang et al., 2008, Bai et al., 2007, Bello et al., 2007, de Ayala Alonso et al., 2007, de Wit et al., 2007, Engström et al., 2007, Goodliffe et al., 2007, Goodliffe et al., 2007, Mishra et al., 2007, Ogasawara et al., 2007, Parrish et al., 2007, Pindyurin et al., 2007, Schuettengruber et al., 2007, Schwartz and Pirrotta, 2007, Song et al., 2007, Chopra and Mishra, 2006, Culi et al., 2006, de Navas et al., 2006, Kang et al., 2006, Kavi et al., 2006, Klymenko et al., 2006, Le Bras and Van Doren, 2006, Liu et al., 2006, Maeda and Karch, 2006, Muller and Kassis, 2006, Papp and Muller, 2006, Qi et al., 2006, Ringrose, 2006, Tolhuis et al., 2006, Wang et al., 2006, Wang et al., 2006, Bejarano et al., 2005, Brown et al., 2005, Canudas et al., 2005, Chanas and Maschat, 2005, Chen et al., 2005, Chen et al., 2005, King et al., 2005, Ali and Bender, 2004, Breiling et al., 2004, Gutierrez et al., 2004, Fischle et al., 2003, Kwon et al., 2003, Balasov, 2002, Huang et al., 2002, Joanis and Lloyd, 2002, King et al., 2002, Fitzgerald and Bender, 2001, Hirose et al., 2001, Choi et al., 2000, Franke et al., 1995)
Name Synonyms
Polycomb
(El-Sharnouby et al., 2017, Schwartz and Cavalli, 2017, Piunti and Shilatifard, 2016, Tie et al., 2016, Wani et al., 2016, Wieschaus and Nüsslein-Volhard, 2016, Bajusz et al., 2015, Kim et al., 2015, Comoglio and Paro, 2014, Gambetta and Müller, 2014, Liu et al., 2014, McElroy et al., 2014, Orsi et al., 2014, Stern et al., 2014, Laver et al., 2013, Lo Sardo et al., 2013, Mulero et al., 2013, Schuettengruber and Cavalli, 2013, Follmer et al., 2012, Herz et al., 2012, Leser et al., 2012, Lim et al., 2012, Mohd-Sarip et al., 2012, Nowak et al., 2012, Petruk et al., 2012, Riddle et al., 2012, Stern et al., 2012, Wen et al., 2012, Anderson et al., 2011, Bantignies et al., 2011, Chen et al., 2011, Crozatier and Vincent, 2011, Davis et al., 2011, Katsuyama and Paro, 2011, Okulski et al., 2011, Strübbe et al., 2011, Tolhuis et al., 2011, Ahn et al., 2010, Baig et al., 2010, Basu and Atchison, 2010, Bhatia et al., 2010, Grau et al., 2010, Herz et al., 2010, Huen and Russell, 2010, Johnson et al., 2010, Kim et al., 2010, Schwartz et al., 2010, Suganuma and Workman, 2010, van Steensel et al., 2010, Wang et al., 2010, Wang et al., 2010, Classen et al., 2009, Fang et al., 2009, Lau et al., 2009, Schaaf et al., 2009, Shevelyov et al., 2009, Sinclair et al., 2009, Sing et al., 2009, Tariq et al., 2009, Zhai et al., 2009, Zhao et al., 2009, Chalkley et al., 2008, Chen et al., 2008, Chen et al., 2008, Chopra and Levine, 2008, Diop et al., 2008, Estella et al., 2008, Fanti et al., 2008, Garaulet et al., 2008, Jung et al., 2008, Kwong et al., 2008, Lu et al., 2008, Pauli et al., 2008, Pindyurin et al., 2008, Zhang et al., 2008, Bello et al., 2007, Bird, 2007, de Wit et al., 2007, Engström et al., 2007, Lanzuolo et al., 2007, Mishra et al., 2007, Pindyurin et al., 2007, Redhouse and White, 2007, Riaz et al., 2007, Ringrose and Paro, 2007, Schuettengruber et al., 2007, Song et al., 2007, Cavalli, 2006, Chopra and Mishra, 2006, Eissenberg, 2006, Kavi et al., 2006, Maeda and Karch, 2006, Maurange et al., 2006, Muller and Kassis, 2006, Negre et al., 2006, Nystul and Spradling, 2006, O'Dor et al., 2006, Ringrose, 2006, Schwartz et al., 2006, Bejarano et al., 2005, Brown et al., 2005, Chen et al., 2005, King et al., 2005, Schwartz et al., 2005, Ali and Bender, 2004, Fischle et al., 2003, Kwon et al., 2003, Levine and Tjian, 2003, Min et al., 2003, Wang and Brock, 2003, Balasov, 2002, Czermin et al., 2002, Huang et al., 2002, Mohd-Sarip et al., 2002, Saller and Bienz, 2001, Choi et al., 2000)
Secondary FlyBase IDs
  • FBgn0015223
  • FBgn0052443
Datasets (3)
Study focus (3)
Experimental Role
Project
Project Type
Title
  • transgene_used
Protein profiling reveals five principal chromatin types in Drosophila cells.
  • bait_protein
Genome-wide localization of chromosomal proteins in cell lines by ChIP-chip and ChIP-Seq.
  • bait_protein
Genome-wide localization of chromosomal proteins in fly tissues by ChIP-chip and ChIP-Seq.
References (897)