FB2026_02 , released June 18, 2026
FB2026_02 , released June 18, 2026
Gene: Dmel\Mst77F
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General Information
Symbol
Dmel\Mst77F
Species
D. melanogaster
Name
Male-specific transcript 77F
Annotation Symbol
CG3354
Feature Type
protein_coding_gene
FlyBase ID
FBgn0086915
Gene Model Status
Current
Stock Availability
6 publicly available
Gene Summary
Male-specific transcript 77F (Mst77F) encodes a sperm component. [Date last reviewed: 2019-03-14] (FlyBase Gene Snapshot)
All Summaries
Also Known As

18c, ms(3)nc3, nc3

Key Links
Genomic Location
Cytogenetic map
77E8-77E8
Sequence location
Recombination map
3-47
RefSeq locus
NT_037436 REGION:20816901..20818027
Sequence
Get Decorated FASTA
Genomic Maps
Other Genome Views
The following external sites may use different assemblies or annotations than FlyBase.
NCBI
UCSC
Ensembl
PopFly
Function
Gene Ontology (GO) Annotations (4 terms)
Molecular Function (0 terms)
Terms Based on Experimental Evidence (0 terms)
Terms Based on Predictions or Assertions (0 terms)
Biological Process (1 term)
Terms Based on Experimental Evidence (1 term)
CV Term
Evidence
References
involved_in sperm DNA condensation
inferred from genetic interaction with FLYBASE:ProtA; FB:FBgn0013300,FLYBASE:ProtB; FB:FBgn0013301
(Kimura and Loppin, 2016)
Terms Based on Predictions or Assertions (0 terms)
Cellular Component (3 terms)
Terms Based on Experimental Evidence (3 terms)
CV Term
Evidence
References
located_in chromatin
inferred from direct assay
(Kimura and Loppin, 2016, Rathke et al., 2010)
located_in nucleus
inferred from direct assay
(Raja and Renkawitz-Pohl, 2005)
located_in sperm flagellum
inferred from direct assay
(Kimura and Loppin, 2016, Rathke et al., 2010, Raja and Renkawitz-Pohl, 2005)
Terms Based on Predictions or Assertions (0 terms)
Gene Group (FlyBase)
Protein Family (UniProt)
-
Protein Signatures (InterPro)
    -
    Summaries
    Gene Snapshot
    Male-specific transcript 77F (Mst77F) encodes a sperm component. [Date last reviewed: 2019-03-14]
    Protein Function (UniProtKB)
    Not known. Encoded in the intron of cAMP-dependent protein kinase regulatory chain type I.
    (UniProt, P16909)
    Phenotypic Description (Red Book; Lindsley and Zimm 1992)
    ms(3)nc3
    Fails to complement certain βTub mutant alleles for male fertility although mapping to another site. Male fertility of homozygotes not determined. ms(3)nc3/+ males fertile.
    Gene Model and Products
    Number of Transcripts
    1
    Number of Unique Polypeptides
    1

    Please see the JBrowse view of Dmel\Mst77F 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 P16909)

    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

    Transcript Data
    Annotated Transcripts
    Name
    FlyBase ID
    RefSeq ID
    Length (nt)
    Assoc. CDS (aa)
    Mst77F-RA
    FBtr0078270
    NM_079464
    1065
    215
    Additional Transcript Data and Comments
    Reported size (kB)

    1.4 (northern blot)

    (Kalderon and Rubin, 1988)
    Comments
    External Data
    Crossreferences
    Polypeptide Data
    Annotated Polypeptides
    Name
    FlyBase ID
    Predicted MW (kDa)
    Length (aa)
    Theoretical pI
    UniProt
    RefSeq ID
    GenBank
    Mst77F-PA
    FBpp0077928
    24.5
    215
    10.46
    P16909
    NP_524188
    AAF51647
    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)

    215 (aa)

    (Kalderon and Rubin, 1988)
    Comments
    External Data
    Crossreferences
    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\Mst77F 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).

    4.19

    Transcript Expression
    in situ
    Stage
    Tissue/Position (including subcellular localization)
    Reference
    spermatogenesis & adult stage | male
    spermatocyte
    (Barckmann et al., 2013)
    elongation stage spermatid
    (Barckmann et al., 2013)
    northern blot
    Stage
    Tissue/Position (including subcellular localization)
    Reference
    pupal stage & adult stage
    (Kalderon and Rubin, 1988)
    Additional Descriptive Data

    Mst77F is expressed at high levels in pupae and adults.

    (Kalderon and Rubin, 1988)
    Marker for
     
    Subcellular Localization
    CV Term
    Polypeptide Expression
    Additional Descriptive Data
    Marker for
     
    Subcellular Localization
    CV Term
    Evidence
    References
    located_in chromatin
    inferred from direct assay
    (Kimura and Loppin, 2016, Rathke et al., 2010)
    located_in nucleus
    inferred from direct assay
    (Raja and Renkawitz-Pohl, 2005)
    located_in sperm flagellum
    inferred from direct assay
    (Kimura and Loppin, 2016, Rathke et al., 2010, Raja and Renkawitz-Pohl, 2005)
    Expression Deduced from Reporters
    High-Throughput Expression Data
    Associated Tools

    JBrowse - Visual display of RNA-Seq signals

    View Dmel\Mst77F in JBrowse
    RNA-Seq by Region - Search RNA-Seq expression levels by exon or genomic region
    Bulk Downloads
    RNA-Seq RPKM values for all genes
    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
    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
    FlyBase Wiki
    Image Based Resources
    Alleles, Insertions, Transgenic Constructs, and Aberrations
    Classical and Insertion Alleles ( 5 )
    For All Classical and Insertion Alleles Show
     
    Other relevant insertions
    Transgenic Constructs ( 21 )
    For All Alleles Carried on Transgenic Constructs Show
    Transgenic constructs containing/affecting coding region of Mst77F
    Transgenic constructs containing regulatory region of Mst77F
    Aberrations (Deficiencies and Duplications) ( 3 )
    Inferred from experimentation ( 3 )
    Gene not disrupted in
    Df(3L)BSC563
    (Kimura and Loppin, 2016)
    Df(3L)ri-79c
    (Kimura and Loppin, 2016)
    Gene disrupted in
    Df(3L)BSC452
    (Kimura and Loppin, 2016)
    Inferred from location ( 3 )
    Variants
    Variant Molecular Consequences
    Alleles Representing Disease-Implicated Variants
    Phenotypes
    For more details about a specific phenotype click on the relevant allele symbol.
    Lethality
    Allele
    partially lethal - majority die, with Scer\GAL4pnr-MD237
    viable, with Dcr-2UAS.cDa, Scer\GAL4elav.PLu
    Sterility
    Allele
    female fertile
    male fertile (with Df(3L)BSC563)
    male fertile (with Df(3L)ri-79c)
    male semi-fertile (with Df(3L)BSC452)
    male semi-fertile (with Mst77FΔ1)
    male semi-fertile (with Mst77FΔ2)
    male semi-fertile (with Mst77FΔ3)
    male sterile
    male sterile (with Df(3L)BSC452)
    male sterile (with Df(3L)BSC797)
    male sterile (with Df(3L)ri-79c)
    male sterile | recessive
    Other Phenotypes
    Allele
    abnormal size | adult stage | male
    some die during pupal stage, with Scer\GAL4pnr-MD237
    Phenotype manifest in
    Allele
    chromatin & late spermatid (with Df(3L)ri-79c)
    chromatin | spermatogenesis
    chromatin | spermatogenesis (with Df(3L)BSC452)
    chromatin | spermatogenesis (with Mst77FΔ1)
    chromatin | spermatogenesis (with Mst77FΔ2)
    cystic bulge
    cystic bulge | spermatogenesis
    cystic bulge | spermatogenesis (with Df(3L)BSC452)
    cystic bulge | spermatogenesis (with Mst77FΔ1)
    cystic bulge | spermatogenesis (with Mst77FΔ2)
    individualization stage spermatid | spermatogenesis
    individualization stage spermatid | spermatogenesis (with Df(3L)BSC452)
    individualization stage spermatid | spermatogenesis (with Mst77FΔ1)
    individualization stage spermatid | spermatogenesis (with Mst77FΔ2)
    male germ cell nucleus
    male germ cell nucleus, with Scer\GAL4path-c135
    nucleus & late spermatid (with Df(3L)ri-79c)
    nucleus & spermatozoon
    nucleus | spermatogenesis
    nucleus | spermatogenesis (with Df(3L)BSC452)
    nucleus | spermatogenesis (with Mst77FΔ1)
    nucleus | spermatogenesis (with Mst77FΔ2)
    seminal vesicle | adult stage
    spermatid
    spermatid, with Scer\GAL4path-c135
    spermatid (with Df(3L)ri-79c)
    spermatid cyst | spermatogenesis
    spermatid cyst | spermatogenesis (with Df(3L)BSC452)
    spermatid cyst | spermatogenesis (with Mst77FΔ1)
    spermatid cyst | spermatogenesis (with Mst77FΔ2)
    spermatozoon, with Scer\GAL4path-c135
    Orthologs
    Downloads
    Download All DIOPT Orthologs
    Human Orthologs (via DIOPT v9.1)
    Species\Gene Symbol
    Score
    Best Score
    Best Reverse Score
    Source
    Compara
    Domainoid
    eggNOG
    Hieranoid
    Homologene
    Inparanoid
    OMA
    OrthoDB
    OrthoFinder
    OrthoInspector
    orthoMCL
    Panther
    Phylome
    SonicParanoid
    Alignment
    Complementation?
    Transgene?
    Homo sapiens (Human) (0)
    Model Organism Orthologs (via DIOPT v9.1)
    Species\Gene Symbol
    Score
    Best Score
    Best Reverse Score
    Source
    Compara
    Domainoid
    eggNOG
    Hieranoid
    Homologene
    Inparanoid
    OMA
    OrthoDB
    OrthoFinder
    OrthoInspector
    orthoMCL
    Panther
    Phylome
    SonicParanoid
    Alignment
    Complementation?
    Transgene?
    Rattus norvegicus (Norway rat) (0)
    Mus musculus (laboratory mouse) (0)
    Xenopus tropicalis (Western clawed frog) (0)
    Danio rerio (Zebrafish) (0)
    Caenorhabditis elegans (Nematode, roundworm) (0)
    Anopheles gambiae (African malaria mosquito) (0)
    Arabidopsis thaliana (thale-cress) (0)
    Saccharomyces cerevisiae (Brewer's yeast) (0)
    Schizosaccharomyces pombe (Fission yeast) (0)
    Escherichia coli (enterobacterium) (0)
    Other Organism Orthologs (via OrthoDB)
    Data provided directly from OrthoDB:Mst77F. Refer to their site for version information.
    Paralogs
    Downloads
    Download All DIOPT Paralogs
    Paralogs (via DIOPT v9.1)
    Gene Symbol
    Score
    Source
    Compara
    Domainoid
    eggNOG
    Homologene
    Inparanoid
    OMA
    OrthoDB
    OrthoFinder
    OrthoInspector
    orthoMCL
    Panther
    Phylome
    SonicParanoid
    Alignment
    Drosophila melanogaster (Fruit fly) (8)
    CG45764
    2 of 13
    CG45765
    2 of 13
    CG45766
    2 of 13
    CG45770
    2 of 13
    Mst77Y-4
    2 of 13
    Mst77Y-7
    2 of 13
    Mst77Y-9
    2 of 13
    Mst77Y-13
    2 of 13
    Human Disease Associations
    FlyBase Human Disease Model Reports
      Disease Ontology (DO) Annotations
      Models Based on Experimental Evidence ( 0 )
      Allele
      Disease
      Evidence
      References
      Potential Models Based on Orthology ( 0 )
      Human Ortholog
      Disease
      Evidence
      References
      Modifiers Based on Experimental Evidence ( 0 )
      Allele
      Disease
      Interaction
      References
      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.
      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.
      Interactions
      Summary of Physical Interactions
      Summary of Genetic Interactions
      Interaction Browsers
      View in FlyBase Interactions Browser   View in MIST tool (external link)
      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
      βTub85D
      enhanceable
      Mst77F
      (Fuller, 1986)
      External Data
      Linkouts
      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
      3-47
      Cytogenetic map
      77E8-77E8
      Sequence location
      FlyBase Computed Cytological Location
      Cytogenetic map
      Evidence for location
      77E8-77E8
      Limits computationally determined from genome sequence between P{EP}trblEP3519 and P{EP}fngEP3082&P{lacW}skdL7062
      Experimentally Determined Cytological Location
      Cytogenetic map
      Notes
      References
      77F-77F
      (Kalderon and Rubin, 1988)
      Experimentally Determined Recombination Data
      Location

      3-47

      (FlyBase, 2016)

      3-43.7

      (Comeron et al., 2012)

      3-47.0 +/- 0.1

      (Fuller, 1986)

      3-[46]

      Left of (cM)
      Right of (cM)
      Notes
      Stocks and Reagents
      Stocks (6)
      Genomic Clones (19)
      cDNA Clones (18)
       

      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
      Other clones
      RNAi and Array Information
      Linkouts
      DRSC - Results frm RNAi screens
      Antibody Information
      Laboratory Generated Antibodies
       

      polyclonal

      (Mao et al., 2025, Park et al., 2023, Zhang et al., 2023, Kimura and Loppin, 2016, Doyen et al., 2013, Rathke et al., 2010)
      Commercially Available Antibodies
       
      Cell Line Information
      Publicly Available Cell Lines
       
        Other Stable Cell Lines
         
          Other Comments

          The Mst77F polypeptide is the first candidate for a specialized DNA binding protein involved in compaction of Drosophila sperm chromatin.

          (Russell and Kaiser, 1993)

          Located within an intron of Pka-R1, transcribed in the opposite orientation to Pka-R1.

          (Kalderon and Rubin, 1988)
          Relationship to Other Genes
          Source for database merge of

          Source for merge of: Mst77F ms(3)nc3

          (Raja and Renkawitz-Pohl, 2005)
          Additional comments

          18 Y-linked genes that are related to the Mst77F gene (which is located on 3L) have been identified. Evidence suggests that these multiple copies originated from a single duplication from the autosome to the Y chromosome, followed by duplications inside the Y. Ten of these Y-linked genes encode defective proteins (Mst77Y-3Ψ, Mst77Y-5Ψ, Mst77Y-6Ψ, Mst77Y-10Ψ, Mst77Y-11Ψ, Mst77Y-14Ψ, Mst77Y-15Ψ, Mst77Y-16Ψ, Mst77Y-17Ψ and Mst77Y-18Ψ) and the other eight are potentially functional (Mst77Y-1, Mst77Y-2, Mst77Y-4, Mst77Y-7, Mst77Y-8, Mst77Y-9, Mst77Y-12 and Mst77Y-13). The eight potentially functional genes produce approximately 20% of the functional Mst77F-like mRNA and evolved under purifying selection.

          (Krsticevic et al., 2010)
          Nomenclature History
          Source for database identify of
          Nomenclature comments
          Etymology
          Synonyms and Secondary IDs (11)
          Datasets (0)
          Study focus (0)
          Experimental Role
          Project
          Project Type
          Title
          Study result (0)
          Result
          Result Type
          Title
          External Crossreferences and Linkouts ( 31 )
          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
          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.
          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
          MIST (protein-protein) - An integrated Molecular Interaction Database
          References (59)