General Information
Symbol
Dmel\sn
Species
D. melanogaster
Name
singed
Annotation Symbol
CG32858
Feature Type
FlyBase ID
FBgn0003447
Gene Model Status
Stock Availability
Gene Snapshot
Singed (Sn) is a member of the fascin family of actin-binding proteins. Fascin proteins organize F-actin into parallel bundles, and are required for the formation of actin-based cellular protrusions. Sn bundling activity is regulated by phosphorylation. [Date last reviewed: 2016-12-01]
Also Known As
fs(1)K418, fs(1)M45
Genomic Location
Cytogenetic map
Sequence location
X:7,964,024..7,986,601 [+]
Recombination map
1-22
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)
Belongs to the fascin family. (Q24524)
Molecular Function (see GO section for details)
Experimental Evidence
-
Predictions / Assertions
Summaries
UniProt Contributed Function Data
Acts as an actin bundling protein (PubMed:1723709, PubMed:19729655). May have a role in the asymmetric organization and/or movement of cytoplasmic components (PubMed:1723709). It has a role in somatic cells during the formation of adult bristles and hairs, and in the female germline during oogenesis (PubMed:1723709, PubMed:19729655).
(UniProt, Q24524)
Phenotypic Description from the Red Book (Lindsley and Zimm 1992)
sn: singed
thumb
sn: singed
From Mohr, 1922, Z. Indukt. Abstamm. Vererbungsl. 28: 1-22.
Macrochaetae deformed, from short and gnarled to wavy, depending on allele. Similarly, microchaetae may be straight or wavy. Electron-microscope examination of developing bristle shaft shows flattened fiber bundles around periphery, which occupy but 5% of cross-sectional profile, compared to wild type, which have fiber bundles that are circular in cross section and occupy 20% of cross-sectional area [Overton, 1967, J. Morph. 122: 367-80 (fig.)]. Females homozygous for the most extreme alleles are completely sterile; vitellogenesis defective. Eggs laid by sn1 homozygotes are normal in number, but are short, blunt, and wrinkled with small blunt dorsal appendages [Mohr, 1922, Z. Indukt. Abstamm. Vererbungsl. 28: 1-22 (fig.)]. Sterility autonomous in transplants (sn1; Clancy and Beadle, 1937, Biol. Bull. 72: 47-56; Perrimon and Gans, 1983, Dev. Biol. 100: 365-73). Heterozygotes between female-sterile and fertile alleles are fertile, between female sterile alleles are sterile.
sn36a
Macrochaetae gnarled in a fairly extreme manner. Microchaetae wild type. sn36a is only allele to cause pronounced reduction in replication of oocyte nurse cell DNA [King and Burnett, 1957, Growth 21: 263-80 (fig.)]. Also causes more extreme retardation of vitellogenesis than other female-sterile sn alleles (Bender). sn36a sn4 homozygote has nearly normal bristles and is sterile. RK1.
sn49
A strong allele of sn recovered from a natural population. Associated with simultaneous mutation to club wing, clw, a defect in wing expansion with low penetrance. sn49 is unstable, producing an array of derivatives that are in turn stable or unstable. and the expression of clw differs among them. It mutates to sn+ and back at a rate of approximately 10-3; a rare moderate singed derivative exhibits an approximately ten-fold elevation in mutation frequency, mutating either back to the strong allele or to an unstable normal allele; a single extreme singed derivative of a normal derivative of the moderate allele produces strong-singed and non-singed derivatives, which can in turn revert to the extreme allele and in the case of the strong derivative to non singed (Yurchenko, Zakharov, and Golubovsky, 1984, Mol. Gen. Genet. 194: 279-85).
sn63-15
Moderate sn phenotype. Prototype type B mutable allele; mutation rate 0.1 to 1.2%. Produces both extreme singed and normal-appearing derivatives as well as an array of intermediate phenotypes. In addition strongly reversible alleles (25-50 x more mutable than parental allele) are produced. This allele also associated with increased rate of mutation to fw.
sn77-27
Extreme sn phenotype. Prototype type A mutable allele; mutates to an unstable sn+, which mutates back to extreme alleles; no intermediate alleles recovered.
sncm
An allele of sn that is mutable in dysgenic but not in non-dysgenic genotypes. Mutation takes place in two directions; one is to apparent stable reversions and the other to a more extreme phenotype, snex, which is in turn unstable.
snw: singed-weak
Weak singed phenotype, probably class 2. Highly mutable in dysgenic genotypes; 40% to 60% of offspring are either normal (sn(+)) or extreme singed (sne) in phenotype. These derivatives are in turn mutable, but at much lower levels. Completely stable in non-dysgenic genotypes.
Gene Model and Products
Number of Transcripts
4
Number of Unique Polypeptides
1

Please see the GBrowse view of Dmel\sn or the JBrowse view of Dmel\sn 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
Low-frequency RNA-Seq exon junction(s) not annotated.
Annotated transcripts do not represent all supported alternative splices within 5' UTR.
Gene model reviewed during 5.50
Sequence Ontology: Class of Gene
Transcript Data
Annotated Transcripts
Name
FlyBase ID
RefSeq ID
Length (nt)
Assoc. CDS (aa)
FBtr0071101
3101
512
FBtr0071102
3358
512
FBtr0301677
2451
512
FBtr0301679
2322
512
Additional Transcript Data and Comments
Reported size (kB)
3.6, 3.3, 3.0 (northern blot)
Comments
External Data
Crossreferences
Polypeptide Data
Annotated Polypeptides
Name
FlyBase ID
Predicted MW (kDa)
Length (aa)
Theoretical pI
RefSeq ID
GenBank
FBpp0071057
57.3
512
7.01
FBpp0071058
57.3
512
7.01
FBpp0290891
57.3
512
7.01
FBpp0290893
57.3
512
7.01
Polypeptides with Identical Sequences

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

512 aa isoforms: sn-PA, sn-PB, sn-PE, sn-PG
Additional Polypeptide Data and Comments
Reported size (kDa)
512 (aa); 57 (kD observed)
512 (aa); 57 (kD predicted)
Comments
Bacterially expressed sn protein is able to bundle F-actin in vitro.
External Data
Subunit Structure (UniProtKB)
Interacts with Rab35, with stronger binding to the Rab35-GTP form compared to the Rab35-GDP form.
(UniProt, Q24524)
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\sn 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 (24 terms)
Molecular Function (3 terms)
Terms Based on Experimental Evidence (0 terms)
Terms Based on Predictions or Assertions (3 terms)
CV Term
Evidence
References
inferred from sequence or structural similarity with UniProtKB:Q16658
(assigned by UniProt )
inferred from sequence or structural similarity
inferred from sequence or structural similarity with UniProtKB:Q16658
(assigned by UniProt )
inferred from biological aspect of ancestor with PANTHER:PTN000058080
(assigned by GO_Central )
inferred from electronic annotation with InterPro:IPR022768, InterPro:IPR024703
(assigned by InterPro )
Biological Process (16 terms)
Terms Based on Experimental Evidence (14 terms)
CV Term
Evidence
References
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
inferred from mutant phenotype
Terms Based on Predictions or Assertions (4 terms)
CV Term
Evidence
References
inferred from biological aspect of ancestor with PANTHER:PTN000058080
(assigned by GO_Central )
inferred from biological aspect of ancestor with PANTHER:PTN000058080
(assigned by GO_Central )
inferred from biological aspect of ancestor with PANTHER:PTN000058080
(assigned by GO_Central )
Cellular Component (5 terms)
Terms Based on Experimental Evidence (5 terms)
CV Term
Evidence
References
inferred from direct assay
inferred from direct assay
inferred from direct assay
inferred from direct assay
colocalizes_with nuclear periphery
inferred from direct assay
(assigned by CACAO )
Terms Based on Predictions or Assertions (1 term)
CV Term
Evidence
References
inferred from biological aspect of ancestor with PANTHER:PTN000058080
(assigned by GO_Central )
Expression Data
Transcript Expression
distribution deduced from reporter
Stage
Tissue/Position (including subcellular localization)
Reference
in situ
Stage
Tissue/Position (including subcellular localization)
Reference
organism | ubiquitous

Comment: maternally deposited

antennal primordium

Comment: reported as procephalic ectoderm primordium

central brain primordium

Comment: reported as procephalic ectoderm primordium

visual primordium

Comment: reported as procephalic ectoderm primordium

dorsal head epidermis primordium

Comment: reported as procephalic ectoderm primordium

lateral head epidermis primordium

Comment: reported as procephalic ectoderm primordium

ventral head epidermis primordium

Comment: reported as procephalic ectoderm primordium

northern blot
Stage
Tissue/Position (including subcellular localization)
Reference
Additional Descriptive Data
sn transcript is expressed in the head (procephalic) mesoderm starting at embryonic stage 8, becoming prominent at stages 9-10. sn transcript is expressed in circulating hemocytes throughout embryogenesis, in the CNS from stage 11, and in epidermal cells forming apical extensions from stage 14-16. sn is not detected in crystal cells.
Marker for
 
Subcellular Localization
CV Term
Polypeptide Expression
distribution deduced from reporter (Gal4 UAS)
Stage
Tissue/Position (including subcellular localization)
Reference
immunolocalization
Stage
Tissue/Position (including subcellular localization)
Reference
mass spectroscopy
Stage
Tissue/Position (including subcellular localization)
Reference
western blot
Stage
Tissue/Position (including subcellular localization)
Reference
Additional Descriptive Data
The sn protein is found in the cytoplasm of nurse cells and the cytoplasm of the developing bristles of the pupa.
sn protein is expressed during oogenesis, and during pupal bristle formation. In stage 9 egg chambers, sn protein is present in border cells and posterior follicle cells. In early stage 10, centripetal follicle cells express sn protein. Although sn protein is present in the nurse cell cytoplasm from early oogenesis, the amounts of the protein increase dramatically early in stage 10. By late stage 10, when the actin filament bundles form, the nurse cell cytoplasm contains high amounts of sn protein, and the high levels persist through stage 11. sn protein is also expressed during bristle formation. In pupae, the cytoplasm of extending bristles and tormogen cells express sn protein.
Marker for
Subcellular Localization
CV Term
Evidence
References
inferred from direct assay
inferred from direct assay
inferred from direct assay
inferred from direct assay
colocalizes_with nuclear periphery
inferred from direct assay
(assigned by CACAO )
Expression Deduced from Reporters
High-Throughput Expression Data
Associated Tools

GBrowse - Visual display of RNA-Seq signals

View Dmel\sn 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
FlyExpress - Embryonic expression images (BDGP data)
  • Stages(s) 1-3
  • Stages(s) 4-6
  • Stages(s) 7-8
  • Stages(s) 9-10
  • Stages(s) 11-12
  • Stages(s) 13-16
Alleles, Insertions, Transgenic Constructs and Phenotypes
Classical and Insertion Alleles ( 206 )
For All Classical and Insertion Alleles Show
 
Allele of sn
Class
Mutagen
Associated Insertion
Stocks
Known lesion
    Yes
      0
      Yes
        0
        --
          0
          Yes
            0
            Yes
              0
              --
              Other relevant insertions
              Transgenic Constructs ( 17 )
              For All Alleles Carried on Transgenic Constructs Show
              Transgenic constructs containing/affecting coding region of sn
              Allele of sn
              Mutagen
              Associated Transgenic Construct
              Stocks
              Transgenic constructs containing regulatory region of sn
              GAL4 construct
              Name
              Expression Data
              reporter construct
              Name
              Expression Data
              Deletions and Duplications ( 39 )
              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
              actin filament & egg chamber
              actin filament & neuron (with sn3)
              actin filament & neuron (with snX2)
              macrochaeta & actin filament
              microchaeta & actin filament
              nurse cell & nucleus
              Orthologs
              Human Orthologs (via DIOPT v7.1)
              Homo sapiens (Human) (3)
              Species\Gene Symbol
              Score
              Best Score
              Best Reverse Score
              Alignment
              Complementation?
              Transgene?
              13 of 15
              Yes
              Yes
              13 of 15
              Yes
              Yes
              5 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?
              13 of 15
              Yes
              Yes
              12 of 15
              No
              Yes
              5 of 15
              No
              Yes
              Rattus norvegicus (Norway rat) (3)
              12 of 13
              Yes
              Yes
              6 of 13
              No
              Yes
              5 of 13
              No
              Yes
              Xenopus tropicalis (Western clawed frog) (2)
              12 of 12
              Yes
              Yes
              7 of 12
              No
              Yes
              Danio rerio (Zebrafish) (4)
              9 of 15
              Yes
              Yes
              9 of 15
              Yes
              Yes
              9 of 15
              Yes
              Yes
              8 of 15
              No
              Yes
              Caenorhabditis elegans (Nematode, roundworm) (3)
              1 of 15
              Yes
              Yes
              1 of 15
              Yes
              No
              1 of 15
              Yes
              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) ( EOG091905JK )
              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 ananassae
              Drosophila pseudoobscura pseudoobscura
              Drosophila willistoni
              Drosophila virilis
              Drosophila mojavensis
              Drosophila grimshawi
              Orthologs in non-Drosophila Dipterans (via OrthoDB v9.1) ( EOG091504JX )
              Organism
              Common Name
              Gene
              Multiple Dmel Genes in this Orthologous Group
              Musca domestica
              House fly
              Glossina morsitans
              Tsetse fly
              Lucilia cuprina
              Australian sheep blowfly
              Mayetiola destructor
              Hessian fly
              Aedes aegypti
              Yellow fever mosquito
              Anopheles darlingi
              American malaria mosquito
              Anopheles gambiae
              Malaria mosquito
              Culex quinquefasciatus
              Southern house mosquito
              Orthologs in non-Dipteran Insects (via OrthoDB v9.1) ( EOG090W040I )
              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) ( EOG090X03X5 )
              Organism
              Common Name
              Gene
              Multiple Dmel Genes in this Orthologous Group
              Strigamia maritima
              European centipede
              Ixodes scapularis
              Black-legged tick
              Stegodyphus mimosarum
              African social velvet spider
              Stegodyphus mimosarum
              African social velvet spider
              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) ( EOG091G0C6S )
              Organism
              Common Name
              Gene
              Multiple Dmel Genes in this Orthologous Group
              Strongylocentrotus purpuratus
              Purple sea urchin
              Strongylocentrotus purpuratus
              Purple sea urchin
              Ciona intestinalis
              Vase tunicate
              Gallus gallus
              Domestic chicken
              Gallus gallus
              Domestic chicken
              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 ( 0 )
                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.
                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
                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)
                Interacts with Rab35, with stronger binding to the Rab35-GTP form compared to the Rab35-GDP form.
                (UniProt, Q24524 )
                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
                1-22
                Cytogenetic map
                Sequence location
                X:7,964,024..7,986,601 [+]
                FlyBase Computed Cytological Location
                Cytogenetic map
                Evidence for location
                7D1-7D2
                Limits computationally determined from genome sequence between P{EP}EP1243 and P{EP}snEP1217
                Experimentally Determined Cytological Location
                Cytogenetic map
                Notes
                References
                7D-7D
                (determined by in situ hybridisation)
                7C1-7D5
                (determined by in situ hybridisation)
                Determined by deficiency mapping (details unspecified).
                Experimentally Determined Recombination Data
                Notes
                Stocks and Reagents
                Stocks (487)
                Genomic Clones (24)
                cDNA Clones (264)
                 

                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
                 
                monoclonal
                Commercially Available Antibodies
                 
                Developmental Studies Hybridoma Bank - Monoclonal antibodies for use in research
                Other Information
                Relationship to Other Genes
                Source for database identify of
                Source for identity of: sn CG1536
                Source for database merge of
                Source for merge of: sn CG15331
                Additional comments
                Annotations CG1536 and CG15331 merged as CG32858 in release 3 of the genome annotation.
                Bender has classified sn alleles into four classes: class 1 = female sterile with gnarled macrochaetae and kinky microchaetae; class 2 = female fertile with kinky macrochaetae only; class 3 = female fertile with gnarled macrochaetae and kinky microchaetae; class 4 = female sterile with gnarled macrochaetae only. To these Golubovsky and Kozlovskaya (1978) have added class 5 = kinky microchaetae only. Derivative alleles have sometimes been designated generically as "snf", "snm", "sns" and "snext", for faint, moderate, strong and extreme phenotypes; these symbols do not specify particular alleles (e.g., Zakharov and Golubovsky, 1984). Unstable alleles also classed as "snA" and "snB", "snA" alleles mutating to normal and back to the original phenotype only and "snB" alleles mutating to an array of intermediate states as well as to normal.
                Other Comments
                sn is an important determinant of class III neuron dendrite morphology, and is necessary for the formation of the characteristic spiked protrusions which are the terminal branchlets of this neuron class.
                dsRNA made from templates generated with primers directed against this gene tested in RNAi screen for effects on Kc167 and S2R+ cell morphology.
                dsRNA made from templates generated with primers directed against this gene is tested in an RNAi screen for effects on actin-based lamella formation.
                Definitive denticle belt phenotypes (abnormal hairs and/or bristles) are foreshadowed by abnormal organisation of the actin cytoskeleton in embryonic epidermal cells.
                One of a class of genes with TATA-less promoters that have a subset of the conserved DPE sequence.
                Single amino acid mutations in the fascin encoded by sn disrupt actin bundling function.
                In(1)T2. ymos wY1 snmY1 strain suppresses y gene mutability and activates sn gene mutability.
                sn is required for actin filament bundle formation in the cytoplasm of nurse cells during oogenesis and for organised actin filament bundle formation in the cellular extension that forms a bristle.
                Mutant sn nurse cells lack actin halo and transport of cytoplasm is blocked.
                Superunstable mutations generated in crosses of π2 strain to a wa strain or its derivatives. Each superunstable mutation gives rise to a large family of new super-unstable mutations with a wide range of phenotypic expression. Mutations with the same phenotype often differ in the specificity of their potential for further mutation. Each superunstable mutation is associated with a specific, "paired", reversible mutation. Active transposase encoded by P elements is necessary to maintain superinstability. X transposable element is also implicated in the mutability system.
                The effects of varying degrees of P-element activity and X irradiation on snw mutability are assessed. Analysis of the combined effects of P-element activity, X irradiation and either excision or post-replication DNA repair on sterility and fecundity is performed.
                Site selected mutagenesis and isolation of sn mutations.
                Four independently obtained families of super-unstable mutations at the sn locus have been studied.
                Alleles show P cytotype-dependent sterility and aberrant oocyte morphology in a P cytotype genetic background.
                Mutations in sn induced by P-M hybrid dysgenesis have been analysed to determine why sn is a hotspot for mutation during P-M hybrid dysgenesis.
                Mutant alleles are useful as markers in clonal analysis.
                Locus divided into three recombinationally different sites from distal to proximal: (sn3 and sn36a) (sn2 and sn4) (sn1, sn5 and sn50k) (Ives and Noyes, 1951; Hexter, 1955a; Hexter, 1955b). Of these, sn3 and sn36a show lesions between -0.9 and 0.0 kb, whereas sn2 has a lesion between 8.0 and 10.5. The others show no detectable molecular lesions and are presumed to be point mutations within the coding region between 11.1 and 13.8 kb.
                Macrochaetae deformed, from short and gnarled to wavy, depending on allele. Similarly, microchaetae may be straight or wavy. Electron-microscope examination of developing bristle shaft shows flattened fiber bundles around periphery, which occupy but 5% of cross-sectional profile, compared to wild type, which have fiber bundles that are circular in cross-section and occupy 20% of cross-sectional area (Overton, 1967). Females homozygous for the most extreme alleles are completely sterile; vitellogenesis defective. Eggs laid by sn1 homozygotes are normal in number, but are short, blunt and wrinkled with small blunt dorsal appendages (Mohr, 1922. Sterility autonomous in transplants (sn1; Clancy and Beadle, 1937; Perrimon and Gans, 1983). Heterozygotes between female-sterile and fertile alleles are fertile, between female sterile alleles are sterile. The sn locus seems to be a very favorable site for P-element insertion; a number of alleles have been isolated from natural populations in the USSR or are derivatives thereof. These alleles are highly mutable, generating innumerable derivative mutable normal-appearing and extreme singed alleles; some have been shown to carry P-element sequences at sn (Golubovsky, Ivanov, and Green, 1977; Green, 1977). Also some display slight increases in the rate of nondisjunction from Basc (Golubovsky, 1983).
                Origin and Etymology
                Discoverer
                Etymology
                Identification
                External Crossreferences and Linkouts ( 56 )
                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
                InterPro - A database of protein families, domains and functional sites
                Linkouts
                BioGRID - A database of protein and genetic interactions.
                Drosophila Genomics Resource Center - Drosophila Genomics Resource Center cDNA clones
                DPiM - Drosophila Protein interaction map
                DroID - A comprehensive database of gene and protein interactions.
                DRSC - Results frm RNAi screens
                Developmental Studies Hybridoma Bank - Monoclonal antibodies for use in research
                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
                Fly-FISH - A database of Drosophila embryo and larvae mRNA localization patterns
                Flygut - An atlas of the Drosophila adult midgut
                FlyMine - An integrated database for Drosophila genomics
                GenomeRNAi - A database for cell-based and in vivo RNAi phenotypes and reagents
                iBeetle-Base - RNAi phenotypes in the red flour beetle (Tribolium castaneum)
                Interactive Fly - A cyberspace guide to Drosophila development and metazoan evolution
                InterologFinder - Protein-protein interactions (PPI) from both known and predicted PPI data sets.
                KEGG Genes - Molecular building blocks of life in the genomic space.
                modMine - A data warehouse for the modENCODE project
                Synonyms and Secondary IDs (16)
                Reported As
                Symbol Synonym
                CG15331
                fs(1)A1057
                fs(1)K1421
                fs(1)K473
                fs(1)K743
                Name Synonyms
                Secondary FlyBase IDs
                • FBgn0040925
                Datasets (0)
                Study focus (0)
                Experimental Role
                Project
                Project Type
                Title
                References (374)