FB2025_02 , released April 17, 2025
Gene: Dmel\apn
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General Information
Symbol
Dmel\apn
Species
D. melanogaster
Name
apnoia
Annotation Symbol
CG15887
Feature Type
protein_coding_gene
FlyBase ID
FBgn0038132
Gene Model Status
Current
Stock Availability
11 publicly available
Gene Summary
Transmembrane protein that plays a key role in trachea development by regulating crb localization and maintenance at the apical cell membrane (PubMed:30645584). Required for anisotropic apical surface expansion important for tracheal tube elongation and lumen stability at larval stages (PubMed:30645584). (UniProt, Q9VFX3)
Contribute a Gene Snapshot for this gene.
All Summaries
Key Links
Genomic Location
Cytogenetic map
87E4-87E4
Sequence location
Recombination map
3-53
RefSeq locus
NT_033777 REGION:13287655..13288813
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 (7 terms)
Molecular Function (1 term)
Terms Based on Experimental Evidence (0 terms)
Terms Based on Predictions or Assertions (0 terms)
Biological Process (6 terms)
Terms Based on Experimental Evidence (6 terms)
CV Term
Evidence
References
involved_in dorsal trunk growth, open tracheal system
inferred from mutant phenotype
(Skouloudaki et al., 2019)
involved_in liquid clearance, open tracheal system
inferred from mutant phenotype
(Skouloudaki et al., 2019)
involved_in lumen formation, open tracheal system
inferred from mutant phenotype
(Skouloudaki et al., 2019)
involved_in open tracheal system development
inferred from mutant phenotype
(Skouloudaki et al., 2019)
involved_in positive regulation of protein localization to membrane
inferred from mutant phenotype
(Skouloudaki et al., 2019)
involved_in trachea development
inferred from mutant phenotype
(Skouloudaki et al., 2019)
inferred from genetic interaction with UniProtKB:P10040
(Skouloudaki et al., 2019)
Terms Based on Predictions or Assertions (0 terms)
Cellular Component (1 term)
Terms Based on Experimental Evidence (1 term)
CV Term
Evidence
References
located_in apical plasma membrane
inferred from direct assay
(Skouloudaki et al., 2019)
Terms Based on Predictions or Assertions (0 terms)
Gene Group (FlyBase)
Protein Family (UniProt)
-
Protein Signatures (InterPro)
    -
    Summaries
    Protein Function (UniProtKB)
    Transmembrane protein that plays a key role in trachea development by regulating crb localization and maintenance at the apical cell membrane (PubMed:30645584). Required for anisotropic apical surface expansion important for tracheal tube elongation and lumen stability at larval stages (PubMed:30645584).
    (UniProt, Q9VFX3)
    Gene Model and Products
    Number of Transcripts
    1
    Number of Unique Polypeptides
    1

    Please see the JBrowse view of Dmel\apn 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 Q9VFX3)

    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 5.47

    Transcript Data
    Annotated Transcripts
    Name
    FlyBase ID
    RefSeq ID
    Length (nt)
    Assoc. CDS (aa)
    apn-RA
    FBtr0082776
    NM_142013
    863
    137
    Additional Transcript Data and Comments
    Reported size (kB)
    Comments
    External Data
    Crossreferences
    Polypeptide Data
    Annotated Polypeptides
    Name
    FlyBase ID
    Predicted MW (kDa)
    Length (aa)
    Theoretical pI
    UniProt
    RefSeq ID
    GenBank
    apn-PA
    FBpp0082244
    14.4
    137
    7.58
    Q9VFX3
    NP_650270
    AAF54922
    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)

    Interacts with crb.

    (UniProt, Q9VFX3)
    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\apn 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).

    -0.27

    Transcript Expression
    Polypeptide Expression
    immunolocalization
    Stage
    Tissue/Position (including subcellular localization)
    Reference
    embryonic stage 13
    tracheal fusion cell
    (Skouloudaki et al., 2019)
    embryonic stage 15 -- 16
    embryonic/larval tracheal dorsal trunk
    (Skouloudaki et al., 2019)
    embryonic/larval tracheal lateral trunk
    (Skouloudaki et al., 2019)
    embryonic/larval visceral tracheal branch
    (Skouloudaki et al., 2019)
    embryonic/larval dorsal tracheal branch
    (Skouloudaki et al., 2019)
    embryonic/larval tracheal transverse connective
    (Skouloudaki et al., 2019)
    larval stage
    larval tracheal system
    (Skouloudaki et al., 2019)
    mass spectroscopy
    Stage
    Tissue/Position (including subcellular localization)
    Reference
    adult stage
    adult head
    (Aradska et al., 2015)
    Additional Descriptive Data

    apn protein is first detected at embryonic stage 13 in tracheal fusion cells. During stages 15 and 16 it is also detected in dorsal and lateral trunks, in the visceral and dorsal branches, and in the transverse connectives.

    (Skouloudaki et al., 2019)
    Marker for
     
    Subcellular Localization
    CV Term
    Evidence
    References
    located_in apical plasma membrane
    inferred from direct assay
    (Skouloudaki et al., 2019)
    Expression Deduced from Reporters
    High-Throughput Expression Data
    Associated Tools

    JBrowse - Visual display of RNA-Seq signals

    View Dmel\apn 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
    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) 13-16
    FlyBase Wiki
    Image Based Resources
    Alleles, Insertions, Transgenic Constructs, and Aberrations
    Classical and Insertion Alleles ( 4 )
    For All Classical and Insertion Alleles Show
     
    Other relevant insertions
    Transgenic Constructs ( 9 )
    For All Alleles Carried on Transgenic Constructs Show
    Transgenic constructs containing/affecting coding region of apn
    Transgenic constructs containing regulatory region of apn
    Aberrations (Deficiencies and Duplications) ( 2 )
    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
    lethal - all die during second instar larval stage
    lethal - all die during second instar larval stage | recessive
    viable, with Dcr-2UAS.cDa, Scer\GAL4elav.PLu
    viable, with Scer\GAL4Mef2.PR
    viable, with Scer\GAL4pnr-MD237
    Other Phenotypes
    Allele
    abnormal cell shape | second instar larval stage
    abnormal size | embryonic stage, with Scer\GAL4btl.PS
    abnormal size | recessive | second instar larval stage
    abnormal size | second instar larval stage
    decreased body size | second instar larval stage
    decreased body size | second instar larval stage, with Scer\GAL4btl.PS
    Phenotype manifest in
    Allele
    embryonic/larval tracheal dorsal trunk | embryonic stage, with Scer\GAL4btl.PS
    embryonic/larval tracheal dorsal trunk | second instar larval stage
    embryonic/larval tracheal lateral trunk | second instar larval stage
    embryonic/larval tracheal section | second instar larval stage
    embryonic/larval tracheal section | second instar larval stage, with Scer\GAL4btl.PS
    embryonic/larval tracheal section | second instar larval stage, with Scer\GAL4da.G32
    embryonic/larval tracheal section | second instar larval stage (with Df(3R)Exel8158)
    extracellular matrix | embryonic stage, with Scer\GAL4btl.PS
    larval tracheocyte | second instar larval stage
    tracheal metamere 8 | second instar larval stage
    tracheal metamere 9 | second instar larval stage
    tracheal metamere 10 | second instar larval stage
    vesicle | second instar larval stage
    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) (3)
    Agam\AgaP_AGAP003419
    9 of 12
    Yes
    Yes
    Agam\AgaP_AGAP013345
    9 of 12
    Yes
    Yes
    Agam\AgaP_AGAP005589
    2 of 12
    No
    No
    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:apn. 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) (1)
    CG14960
    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
      Interaction Browsers
      View in FlyBase Interactions Browser   View in MIST tool (external link)
      Please see the Physical Interaction reports below for full details
      protein-protein
      Physical Interaction
      Assay
      References
      apn - crb
      ubiquitin reconstruction, anti bait coimmunoprecipitation, western blot, proximity ligation assay, fluorescence microscopy
      (Skouloudaki et al., 2019)
      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
      apn
      suppressible
      crb
      (Skouloudaki et al., 2019)
      Starting gene(s)
      Interaction type
      Interacting gene(s)
      Reference
      External Data
      Subunit Structure (UniProtKB)
      Interacts with crb.
      (UniProt, Q9VFX3 )
      Linkouts
      DroID - A comprehensive database of gene and protein interactions.
      Pathways
      Signaling Pathways (FlyBase)
      Metabolic Pathways
      FlyBase
      External Links
      External Data
      Linkouts
      Class of Gene
      Genomic Location and Detailed Mapping Data
      Chromosome (arm)
      3R
      Recombination map
      3-53
      Cytogenetic map
      87E4-87E4
      Sequence location
      FlyBase Computed Cytological Location
      Cytogenetic map
      Evidence for location
      87E4-87E4
      Limits computationally determined from genome sequence between P{PZ}CtBP03463 and P{lacW}B52s2249&P{lacW}flflL4179
      Experimentally Determined Cytological Location
      Cytogenetic map
      Notes
      References
      Experimentally Determined Recombination Data
      Location

      3-53

      (FlyBase, 2016)

      3-50.8

      (Comeron et al., 2012)
      Left of (cM)
      Right of (cM)
      Notes
      Stocks and Reagents
      Stocks (11)
      Genomic Clones (22)
      cDNA Clones (14)
       

      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

        (Scholl et al., 2019, Skouloudaki et al., 2019)
        Commercially Available Antibodies
         
        Cell Line Information
        Publicly Available Cell Lines
         
          Other Stable Cell Lines
           
            Other Comments
            Relationship to Other Genes
            Source for database merge of

            Source for merge of: CG15887 BcDNA:RE53127

            (FlyBase, 1996-)
            Additional comments

            Source for merge of CG15887 BcDNA:RE53127 was TrEMBL update ( date:020807 ).

            (FlyBase, 1996-)
            Nomenclature History
            Source for database identify of

            Source for identity of: apn CG15887

            (Skouloudaki et al., 2019)
            Nomenclature comments
            Etymology

            Named 'apnoia' based on the defects in tracheal growth and inflation seen in mutants during larval stages.

            (Skouloudaki et al., 2019)
            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 ( 26 )
            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.
            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)
            References (27)