FB2025_02 , released April 17, 2025
Gene: Dmel\st
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General Information
Symbol
Dmel\st
Species
D. melanogaster
Name
scarlet
Annotation Symbol
CG4314
Feature Type
FlyBase ID
FBgn0003515
Gene Model Status
Stock Availability
Gene Summary
ATP-dependent transporter of the ATP-binding cassette (ABC) family which transports various molecules including bioamines, neurotransmitters and metabolic intermediates (PubMed:18931318, PubMed:33820991, PubMed:812484). In the eye and probably in association with w/white, required for the transport of the eye brown pigment precursors, kynurenine and probably tryptophan, into pigment cell granules (PubMed:10407069, PubMed:812484). In Malpighian tubules and pupal eyes, involved in kynurenine transport (PubMed:812484). Probably in association with w/white, plays a role in zinc storage granule biogenesis in Malpighian tubule principal epithelial cells (PubMed:29367274). (UniProt, P45843)
Contribute a Gene Snapshot for this gene.
Key Links
Genomic Location
Cytogenetic map
Sequence location
Recombination map
3-44
RefSeq locus
NT_037436 REGION:16497651..16500460
Sequence
Genomic Maps
Other Genome Views
The following external sites may use different assemblies or annotations than FlyBase.
Function
Gene Ontology (GO) Annotations (13 terms)
Molecular Function (6 terms)
Terms Based on Experimental Evidence (2 terms)
CV Term
Evidence
References
inferred from mutant phenotype
Terms Based on Predictions or Assertions (4 terms)
CV Term
Evidence
References
Biological Process (3 terms)
Terms Based on Experimental Evidence (3 terms)
CV Term
Evidence
References
inferred from expression pattern
inferred from mutant phenotype
Terms Based on Predictions or Assertions (2 terms)
CV Term
Evidence
References
traceable author statement
inferred from electronic annotation with InterPro:IPR005284
inferred from biological aspect of ancestor with PANTHER:PTN008283605
Cellular Component (4 terms)
Terms Based on Experimental Evidence (1 term)
CV Term
Evidence
References
inferred from direct assay
Terms Based on Predictions or Assertions (3 terms)
CV Term
Evidence
References
inferred from biological aspect of ancestor with PANTHER:PTN008729989
located_in membrane
inferred from electronic annotation with InterPro:IPR005284, InterPro:IPR013525
is_active_in plasma membrane
inferred from biological aspect of ancestor with PANTHER:PTN000443095
Protein Family (UniProt)
Belongs to the ABC transporter superfamily. ABCG family. Eye pigment precursor importer (TC 3.A.1.204) subfamily. (P45843)
Catalytic Activity (EC/Rhea)
ATP hydrolysis activity
RHEA 13065:
Summaries
Gene Group (FlyBase)
ABCG ATP-BINDING CASSETTE TRANSPORTER SUBFAMILY -
The ATP-binding cassette (ABC) transporter family are primary active transporters that use ATP hydrolysis to drive the transport of substrates across the membrane. In metazoans the ABCG subfamily are half transporters. Half transporters must dimerize to form a functional transporter. (Adapted from FBrf0224053).
Protein Function (UniProtKB)
ATP-dependent transporter of the ATP-binding cassette (ABC) family which transports various molecules including bioamines, neurotransmitters and metabolic intermediates (PubMed:18931318, PubMed:33820991, PubMed:812484). In the eye and probably in association with w/white, required for the transport of the eye brown pigment precursors, kynurenine and probably tryptophan, into pigment cell granules (PubMed:10407069, PubMed:812484). In Malpighian tubules and pupal eyes, involved in kynurenine transport (PubMed:812484). Probably in association with w/white, plays a role in zinc storage granule biogenesis in Malpighian tubule principal epithelial cells (PubMed:29367274).
(UniProt, P45843)
Phenotypic Description (Red Book; Lindsley and Zimm 1992)
st: scarlet
Eyes bright vermilion, darkening with age. Ocelli colorless, even in old fly; a reliable trait for classifying st se. Eyes of bw; st white. Eye color autonomous in larval optic disks transplanted into wild-type hosts (Beadle and Ephrussi, 1936, Genetics 21: 230). Larval Malpighian tubes pale yellow (Beadle, 1937, Genetics 22: 587-611). Phenocritical period, as indicated by temperature-shift experiments utilizing st12, is 24-48 h after pupariation at 25 (Howells, 1973). Uptake of kynurenine by Malpighian tubules and eye disks severely deficient (Sullivan and Sullivan, 1975, Biochem. Genet. 13: 603-13). 3-hydroxykynurenine accumulates only in pupae; virtually undetectable in larvae and adults (Howells and Ryall, 1976, Biochem. Genet. 14: 1077-90). Activity of phenoxazinone synthetase, which is found in pigment granules and which catalyzes the bimolecular condensation of 3-hydroxykynurenine in the production of brown eye pigment, xanthommatin, markedly reduced in st (Phillips, Forrest, and Kulkarni, 1973, Genetics 73: 45-56). RK1.
st12
Scarlet eyes at 29; normal eye color at 18; xanthommatin levels 9% and 72% of wild type respectively (Howells, 1979, Biochem. Genet. 17: 149-58).
stsp: scarlet-spotted
Eyes scarlet with facets and groups of facets that appear wild type. Darkening spreads in old fly. Not a variegated position effect. stsp/st like stsp. Larval Malpighian tubules pale yellow and classifiable (Brehme and Demerec, 1942, Growth 6: 351-56). RK2.
Gene Model and Products
Number of Transcripts
1
Number of Unique Polypeptides
1

Please see the JBrowse view of Dmel\st 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
Structure
Protein 3D structure   (Predicted by AlphaFold)   (AlphaFold entry P45843)

If you don't see a structure in the viewer, refresh your browser.
Model Confidence:
  • Very high (pLDDT > 90)
  • Confident (90 > pLDDT > 70)
  • Low (70 > pLDDT > 50)
  • Very low (pLDDT < 50)

AlphaFold produces a per-residue confidence score (pLDDT) between 0 and 100. Some regions with low pLDDT may be unstructured in isolation.

Experimentally Determined Structures
Crossreferences
Comments on Gene Model

Gene model reviewed during 5.45

Gene model reviewed during 5.55

Transcript Data
Annotated Transcripts
Name
FlyBase ID
RefSeq ID
Length (nt)
Assoc. CDS (aa)
FBtr0075391
2146
666
Additional Transcript Data and Comments
Reported size (kB)

2.3 (northern blot)

Comments
External Data
Crossreferences
Polypeptide Data
Annotated Polypeptides
Name
FlyBase ID
Predicted MW (kDa)
Length (aa)
Theoretical pI
UniProt
RefSeq ID
GenBank
FBpp0075149
74.5
666
7.48
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)
Comments
External Data
Subunit Structure (UniProtKB)

May form a heterodimer with w/white.

(UniProt, P45843)
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\st using the Feature Mapper tool.

External Data
Crossreferences
Eukaryotic Promoter Database - A collection of databases of experimentally validated promoters for selected model organisms.
Linkouts
Expression Data
Testis-specificity index

The testis specificity index was calculated from modENCODE tissue expression data by Vedelek et al., 2018 to indicate the degree of testis enrichment compared to other tissues. Scores range from -2.52 (underrepresented) to 5.2 (very high testis bias).

-0.14

Transcript Expression
No Assay Recorded
Stage
Tissue/Position (including subcellular localization)
Reference
in situ
Stage
Tissue/Position (including subcellular localization)
Reference
Additional Descriptive Data

st transcripts are expressed at low levels throughout development with a peak of expression in early to mid-pupal stages. The st transcript level is not altered substantially in a w1 mutant backgound.

A transcript that is slightly smaller and less abundant than wild type is seen in st1 mutant pupae.

The st transcript is present at 5% of the wild type level in stsp mutant pupae.

Marker for
 
Subcellular Localization
CV Term
Polypeptide Expression
mass spectroscopy
Stage
Tissue/Position (including subcellular localization)
Reference
Additional Descriptive Data
Marker for
 
Subcellular Localization
CV Term
Evidence
References
inferred from direct assay
Expression Deduced from Reporters
High-Throughput Expression Data
Associated Tools

JBrowse - Visual display of RNA-Seq signals

View Dmel\st in JBrowse
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
DRscDB - A single-cell RNA-seq resource for data mining and data comparison across species
EMBL-EBI Single Cell Expression Atlas - Single cell expression across species
FlyAtlas - Adult expression by tissue, using Affymetrix Dros2 array
FlyAtlas2 - A Drosophila melanogaster expression atlas with RNA-Seq, miRNA-Seq and sex-specific data
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) 11-12
  • Stages(s) 13-16
Alleles, Insertions, Transgenic Constructs, and Aberrations
Classical and Insertion Alleles ( 51 )
For All Classical and Insertion Alleles Show
 
Other relevant insertions
Transgenic Constructs ( 8 )
For All Alleles Carried on Transgenic Constructs Show
Transgenic constructs containing/affecting coding region of st
Transgenic constructs containing regulatory region of st
Aberrations (Deficiencies and Duplications) ( 60 )
Inferred from experimentation ( 60 )
Gene disrupted in
Inferred from location ( 6 )
Variants
Variant Molecular Consequences
Alleles Representing Disease-Implicated Variants
Phenotypes
Orthologs
Human Orthologs (via DIOPT v9.1)
Species\Gene Symbol
Score
Best Score
Best Reverse Score
Alignment
Complementation?
Transgene?
Homo sapiens (Human) (9)
8 of 14
Yes
Yes
7 of 14
No
No
6 of 14
No
No
5 of 14
No
No
4 of 14
No
No
1 of 14
No
No
1  
1 of 14
No
No
1  
1 of 14
No
No
1 of 14
No
No
Model Organism Orthologs (via DIOPT v9.1)
Species\Gene Symbol
Score
Best Score
Best Reverse Score
Alignment
Complementation?
Transgene?
Rattus norvegicus (Norway rat) (9)
7 of 14
Yes
No
7 of 14
Yes
Yes
6 of 14
No
No
6 of 14
No
No
5 of 14
No
No
5 of 14
No
No
5 of 14
No
No
1 of 14
No
Yes
1 of 14
No
Yes
Mus musculus (laboratory mouse) (6)
8 of 14
Yes
Yes
7 of 14
No
No
6 of 14
No
No
5 of 14
No
No
5 of 14
No
No
5 of 14
No
No
Xenopus tropicalis (Western clawed frog) (5)
4 of 13
Yes
No
3 of 13
No
No
3 of 13
No
No
3 of 13
No
No
1 of 13
No
No
Danio rerio (Zebrafish) (9)
7 of 14
Yes
No
7 of 14
Yes
No
7 of 14
Yes
No
7 of 14
Yes
No
7 of 14
Yes
Yes
6 of 14
No
No
5 of 14
No
No
5 of 14
No
No
4 of 14
No
No
Caenorhabditis elegans (Nematode, roundworm) (13)
7 of 14
Yes
No
7 of 14
Yes
Yes
7 of 14
Yes
No
7 of 14
Yes
Yes
6 of 14
No
No
6 of 14
No
No
6 of 14
No
No
5 of 14
No
No
4 of 14
No
No
3 of 14
No
No
1 of 14
No
No
1 of 14
No
No
1 of 14
No
Yes
Anopheles gambiae (African malaria mosquito) (27)
12 of 12
Yes
Yes
5 of 12
No
No
Arabidopsis thaliana (thale-cress) (50)
9 of 13
Yes
Yes
6 of 13
No
No
6 of 13
No
No
6 of 13
No
No
6 of 13
No
No
6 of 13
No
No
6 of 13
No
No
6 of 13
No
No
5 of 13
No
No
5 of 13
No
No
5 of 13
No
Yes
5 of 13
No
Yes
5 of 13
No
No
5 of 13
No
Yes
5 of 13
No
No
5 of 13
No
No
5 of 13
No
No
5 of 13
No
No
5 of 13
No
No
5 of 13
No
No
5 of 13
No
No
5 of 13
No
No
5 of 13
No
No
5 of 13
No
No
5 of 13
No
Yes
3 of 13
No
Yes
3 of 13
No
No
3 of 13
No
No
3 of 13
No
No
2 of 13
No
No
2 of 13
No
No
2 of 13
No
No
2 of 13
No
No
2 of 13
No
No
2 of 13
No
No
2 of 13
No
No
2 of 13
No
No
2 of 13
No
No
2 of 13
No
No
2 of 13
No
No
2 of 13
No
No
2 of 13
No
No
2 of 13
No
Yes
2 of 13
No
No
1 of 13
No
No
1 of 13
No
No
1 of 13
No
No
1 of 13
No
No
1 of 13
No
No
1 of 13
No
No
Saccharomyces cerevisiae (Brewer's yeast) (10)
6 of 13
Yes
No
6 of 13
Yes
No
4 of 13
No
No
4 of 13
No
No
4 of 13
No
No
4 of 13
No
No
4 of 13
No
No
3 of 13
No
No
3 of 13
No
No
3 of 13
No
No
Schizosaccharomyces pombe (Fission yeast) (2)
5 of 12
Yes
Yes
3 of 12
No
No
Escherichia coli (enterobacterium) (21)
1 of 11
Yes
No
1 of 11
Yes
No
1 of 11
Yes
No
1 of 11
Yes
Yes
1 of 11
Yes
No
1 of 11
Yes
Yes
1 of 11
Yes
Yes
1 of 11
Yes
No
1 of 11
Yes
No
1 of 11
Yes
No
1 of 11
Yes
No
1 of 11
Yes
No
1 of 11
Yes
No
1 of 11
Yes
No
1 of 11
Yes
Yes
1 of 11
Yes
Yes
1 of 11
Yes
No
1 of 11
Yes
No
1 of 11
Yes
Yes
1 of 11
Yes
Yes
1 of 11
Yes
Yes
Other Organism Orthologs (via OrthoDB)
Data provided directly from OrthoDB:st. Refer to their site for version information.
Paralogs
Paralogs (via DIOPT v9.1)
Drosophila melanogaster (Fruit fly) (19)
10 of 13
8 of 13
8 of 13
8 of 13
8 of 13
7 of 13
7 of 13
7 of 13
7 of 13
7 of 13
7 of 13
5 of 13
5 of 13
5 of 13
1 of 13
1 of 13
1 of 13
1 of 13
1 of 13
Human Disease Associations
FlyBase Human Disease Model Reports
Disease Ontology (DO) Annotations
Models Based on Experimental Evidence ( 6 )
Potential Models Based on Orthology ( 2 )
Human Ortholog
Disease
Evidence
References
Modifiers Based on Experimental Evidence ( 2 )
Disease Associations of Human Orthologs (via DIOPT v9.1 and OMIM)
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
Interaction Browsers
Summary of Genetic Interactions
Interaction Browsers

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)
May form a heterodimer with w/white.
(UniProt, P45843 )
Linkouts
BioGRID - A database of protein and genetic interactions.
DroID - A comprehensive database of gene and protein interactions.
MIST (protein-protein) - An integrated Molecular Interaction Database
Pathways
Signaling Pathways (FlyBase)
Metabolic Pathways
FlyBase
External Links
External Data
Linkouts
Class of Gene
Genomic Location and Detailed Mapping Data
Chromosome (arm)
3L
Recombination map
3-44
Cytogenetic map
Sequence location
FlyBase Computed Cytological Location
Cytogenetic map
Evidence for location
73A3-73A3
Limits computationally determined from genome sequence between P{lacW}l(3)j10E8j10E8&P{PZ}l(3)1053210532 and P{PZ}Baldspot02281
Experimentally Determined Cytological Location
Cytogenetic map
Notes
References
73A3-73A4
(determined by in situ hybridisation)
Experimentally Determined Recombination Data
Location

3-44.0

Notes
Stocks and Reagents
Stocks (664)
Genomic Clones (30)
cDNA Clones (9)
 

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 JBrowse for alignment of the cDNAs and ESTs to the gene model.

cDNA clones, fully sequenced
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)
BDGP DGC clones
RNAi and Array Information
Linkouts
DRSC - Results frm RNAi screens
Antibody Information
Laboratory Generated Antibodies
 
Commercially Available Antibodies
 
Cell Line Information
Publicly Available Cell Lines
 
    Other Stable Cell Lines
     
      Other Comments

      st protein is located in the membranes of pigment granules within pigment cells and retinula cells of the eye. No evidence of its presence in the plasma membrane has been seen.

      Transcripts of bw, st and w are all modulated by Inr-b in a developmentally-specific manner.

      Eyes bright vermilion, darkening with age. Ocelli colorless, even in old fly; a reliable trait for classifying st se. Eyes of bw; st white. Eye color autonomous in larval optic discs transplanted into wild-type hosts. Larval Malpighian tubes pale yellow. Uptake of kynurenine by Malpighian tubules and eye discs severely deficient. 3-hydroxykynurenine accumulates only in pupae; virtually undetectable in larvae and adults. Activity of phenoxazinone synthetase, which is found in pigment granules and which catalyzes the bimolecular condensation of 3-hydroxykynurenine in the production of brown eye pigment, xanthommatin, markedly reduced in st.

      st is required for the synthesis of ommochrome in any tissue and is involved in the transport of pigmentation precursors.

      Lesions in st reduce or eliminate pigmentation in the eyes and ocelli and block pigmentation of the fat body and tubules.

      Similarity of w and st mutant phenotypes may reflect a common biochemical function for the gene products. st gene performs no function essential for viability.

      Mutant alleles are useful as markers in clonal analysis.

      Pteridines (neodrosopterin, drosopterin, isodrosopterin, aurodrosopterin, 6-acetyl-dihydrohomopterin, sepiapterin, dihydrobiopterin, biopterin, pterin and isoxanthopterin) have been quantified in single and double mutants.

      Mutant individuals display bright red eyes.

      Relationship to Other Genes
      Source for database merge of
      Additional comments
      Nomenclature History
      Source for database identify of
      Nomenclature comments
      Etymology
      Synonyms and Secondary IDs (6)
      Datasets (0)
      Study focus (0)
      Experimental Role
      Project
      Project Type
      Title
      Study result (0)
      Result
      Result Type
      Title
      External Crossreferences and Linkouts ( 42 )
      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/GCRP - The gene-centric reference proteome (GCRP) provides a 1:1 mapping between genes and UniProt accessions in which a single 'canonical' isoform represents the product(s) of each protein-coding gene.
      UniProt/Swiss-Prot - Manually annotated and reviewed records of protein sequence and functional information
      Other crossreferences
      AlphaFold DB - AlphaFold provides open access to protein structure predictions for the human proteome and other key proteins of interest, to accelerate scientific research.
      BDGP expression data - Patterns of gene expression in Drosophila embryogenesis
      DRscDB - A single-cell RNA-seq resource for data mining and data comparison across species
      EMBL-EBI Single Cell Expression Atlas - Single cell expression across species
      FlyAtlas2 - A Drosophila melanogaster expression atlas with RNA-Seq, miRNA-Seq and sex-specific data
      FlyMine - An integrated database for Drosophila genomics
      KEGG Genes - Molecular building blocks of life in the genomic space.
      MARRVEL_MODEL - MARRVEL (model organism gene)
      Linkouts
      BioGRID - A database of protein and genetic interactions.
      Drosophila Genomics Resource Center - Drosophila Genomics Resource Center (DGRC) cDNA clones
      DroID - A comprehensive database of gene and protein interactions.
      DRSC - Results frm RNAi screens
      Eukaryotic Promoter Database - A collection of databases of experimentally validated promoters for selected model organisms.
      FlyAtlas - Adult expression by tissue, using Affymetrix Dros2 array
      FlyCyc Genes - Genes from a BioCyc PGDB for Dmel
      Fly-FISH - A database of Drosophila embryo and larvae mRNA localization patterns
      Flygut - An atlas of the Drosophila adult midgut
      iBeetle-Base - RNAi phenotypes in the red flour beetle (Tribolium castaneum)
      MIST (protein-protein) - An integrated Molecular Interaction Database
      References (198)