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General Information
Symbol
Dmel\trk
Species
D. melanogaster
Name
trunk
Annotation Symbol
CG5619
Feature Type
FlyBase ID
FBgn0003751
Gene Model Status
Stock Availability
Gene Summary
trunk (trk) encodes one of its cleaved forms acts as the ligand for the receptor encoded by tor in the early embryo. [Date last reviewed: 2019-03-14] (FlyBase Gene Snapshot)
Also Known As

fs(2)trunk

Key Links
Genomic Location
Cytogenetic map
Sequence location
Recombination map
2-40
RefSeq locus
NT_033779 REGION:10271443..10272324
Sequence
Other Genome Views
The following external sites may use different assemblies or annotations than FlyBase.
Function
GO Summary Ribbons
Gene Ontology (GO) Annotations (6 terms)
Molecular Function (3 terms)
Terms Based on Experimental Evidence (2 terms)
CV Term
Evidence
References
inferred from direct assay
inferred from direct assay
Terms Based on Predictions or Assertions (1 term)
CV Term
Evidence
References
inferred from biological aspect of ancestor with PANTHER:PTN002219116
(assigned by GO_Central )
Biological Process (2 terms)
Terms Based on Experimental Evidence (2 terms)
CV Term
Evidence
References
Terms Based on Predictions or Assertions (0 terms)
Cellular Component (1 term)
Terms Based on Experimental Evidence (1 term)
CV Term
Evidence
References
inferred from direct assay
Terms Based on Predictions or Assertions (0 terms)
Gene Group (FlyBase)
Protein Family (UniProt)
Belongs to the noggin family. (Q24155)
Protein Signatures (InterPro)
Summaries
Gene Snapshot
trunk (trk) encodes one of its cleaved forms acts as the ligand for the receptor encoded by tor in the early embryo. [Date last reviewed: 2019-03-14]
Pathway (FlyBase)
Torso Signaling Pathway Core Components -
The formation of Drosophila embryonic termini is controlled by the localized activation of Torso (tor) receptor tyrosine kinase. The Torso signaling pathway acts via the canonical Ras/Raf/MAP kinase cascade. (Adapted from FBrf0157176.)
Gene Group (FlyBase)
UNCLASSIFIED RECEPTOR LIGANDS -
Receptor ligands are endogenous polypeptides that bind transmembrane cell surface receptors to elicit a cellular response.
Protein Function (UniProtKB)
Required for activity of the tor receptor, could be a ligand of tor. Involved in specifying terminal body pattern.
(UniProt, Q24155)
Phenotypic Description (Red Book; Lindsley and Zimm 1992)
trk: trunk (T. Schupbach)
Maternal-effect lethal; embryos from homozygous mothers lack anterior-most head structures and structures posterior to the seventh abdominal segment. At gastrulation cephalic furrow is shifted toward anterior and the germband extends all the way to the posterior end. During cellularization at the blastoderm stage a funnel of yolk free cytoplasm containing a small number of nuclei (between 10 and 30) forms at the posterior pole of the embryos extending from the egg periphery to the inner yolk mass. Analysis of germline clones indicates that the mutation is germline autonomous (Schupbach and Wieschaus, 1986, Dev. Biol. 113: 443-48).
Summary (Interactive Fly)

secreted - ligand for torso - crucial for establishment of anterior and posterior cell identity of the embryo - Trunk and Torsolike alone are ineffective but acted synergistically to stimulate Torso signaling

Gene Model and Products
Number of Transcripts
1
Number of Unique Polypeptides
1

Please see the JBrowse view of Dmel\trk for information on other features

To submit a correction to a gene model please use the Contact FlyBase form

Protein Domains (via Pfam)
Isoform displayed:
Pfam protein domains
InterPro name
classification
start
end
Protein Domains (via SMART)
Isoform displayed:
SMART protein domains
InterPro name
classification
start
end
Comments on Gene Model

Gene model reviewed during 5.46

Sequence Ontology: Class of Gene
Transcript Data
Annotated Transcripts
Name
FlyBase ID
RefSeq ID
Length (nt)
Assoc. CDS (aa)
FBtr0080078
882
235
Additional Transcript Data and Comments
Reported size (kB)

0.8 (northern blot)

Comments
External Data
Crossreferences
Polypeptide Data
Annotated Polypeptides
Name
FlyBase ID
Predicted MW (kDa)
Length (aa)
Theoretical pI
RefSeq ID
GenBank
FBpp0079667
27.4
235
8.25
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
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\trk 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
Expression Summary Ribbons
Colored tiles in ribbon indicate that expression data has been curated by FlyBase for that anatomical location. Colorless tiles indicate that there is no curated data for that location.
For complete stage-specific expression data, view the modENCODE Development RNA-Seq section under High-Throughput Expression below.
Transcript Expression
in situ
Stage
Tissue/Position (including subcellular localization)
Reference
organism | ubiquitous

Comment: reference states 0-2 hr AEL

Additional Descriptive Data

trk transcripts are present in nurse cells but not follicle cells during oogenesis and are ubiquitous in early embryos.

Marker for
 
Subcellular Localization
CV Term
Polypeptide Expression
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

GBrowse - Visual display of RNA-Seq signals

View Dmel\trk 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
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
Flygut - An atlas of the Drosophila adult midgut
Images
Alleles, Insertions, Transgenic Constructs, and Aberrations
Classical and Insertion Alleles ( 17 )
For All Classical and Insertion Alleles Show
 
Other relevant insertions
Transgenic Constructs ( 33 )
For All Alleles Carried on Transgenic Constructs Show
Transgenic constructs containing/affecting coding region of trk
Transgenic constructs containing regulatory region of trk
Aberrations (Deficiencies and Duplications) ( 15 )
Alleles Representing Disease-Implicated Variants
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
Orthologs
Human Orthologs (via DIOPT v8.0)
Homo sapiens (Human) (1)
Species\Gene Symbol
Score
Best Score
Best Reverse Score
Alignment
Complementation?
Transgene?
1 of 15
Yes
Yes
Model Organism Orthologs (via DIOPT v8.0)
Mus musculus (laboratory mouse) (0)
No records found.
Rattus norvegicus (Norway rat) (1)
1 of 13
Yes
Yes
Xenopus tropicalis (Western clawed frog) (3)
1 of 12
Yes
Yes
1 of 12
Yes
Yes
1 of 12
Yes
Yes
Danio rerio (Zebrafish) (4)
1 of 15
Yes
Yes
1 of 15
Yes
Yes
1 of 15
Yes
Yes
1 of 15
Yes
Yes
Caenorhabditis elegans (Nematode, roundworm) (1)
1 of 15
Yes
Yes
Arabidopsis thaliana (thale-cress) (0)
No records found.
Saccharomyces cerevisiae (Brewer's yeast) (0)
No records found.
Schizosaccharomyces pombe (Fission yeast) (0)
No records found.
Ortholog(s) in Drosophila Species (via OrthoDB v9.1) ( EOG09190E00 )
Organism
Common Name
Gene
AAA Syntenic Ortholog
Multiple Dmel Genes in this Orthologous Group
Drosophila simulans
Drosophila erecta
Drosophila yakuba
Drosophila ananassae
Drosophila pseudoobscura pseudoobscura
Drosophila persimilis
Drosophila willistoni
Drosophila virilis
Drosophila mojavensis
Drosophila grimshawi
Orthologs in non-Drosophila Dipterans (via OrthoDB v9.1) ( EOG09150D73 )
Organism
Common Name
Gene
Multiple Dmel Genes in this Orthologous Group
Musca domestica
House 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) ( EOG090W08AO )
Organism
Common Name
Gene
Multiple Dmel Genes in this Orthologous Group
Linepithema humile
Argentine ant
Megachile rotundata
Alfalfa leafcutting bee
Nasonia vitripennis
Parasitic wasp
Tribolium castaneum
Red flour beetle
Tribolium castaneum
Red flour beetle
Cimex lectularius
Bed bug
Acyrthosiphon pisum
Pea aphid
Orthologs in non-Insect Arthropods (via OrthoDB v9.1) ( EOG090X0FWG )
Organism
Common Name
Gene
Multiple Dmel Genes in this Orthologous Group
Strigamia maritima
European centipede
Orthologs in non-Arthropod Metazoa (via OrthoDB v9.1) ( None identified )
No non-Arthropod Metazoa orthologies identified
Paralogs
Paralogs (via DIOPT v8.0)
Drosophila melanogaster (Fruit fly) (1)
1 of 10
Human Disease Associations
FlyBase Human Disease Model Reports
    Disease Model Summary Ribbon
    Disease Ontology (DO) Annotations
    Models Based on Experimental Evidence ( 0 )
    Allele
    Disease
    Evidence
    References
    Potential Models Based on Orthology ( 0 )
    Human Ortholog
    Disease
    Evidence
    References
    Modifiers Based on Experimental Evidence ( 0 )
    Allele
    Disease
    Interaction
    References
    Disease Associations of Human Orthologs (via DIOPT v8.0 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
    esyN Network Diagram
    Interactions Browser
    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
    Linkouts
    BioGRID - A database of protein and genetic interactions.
    DroID - A comprehensive database of gene and protein interactions.
    MIST (genetic) - An integrated Molecular Interaction Database
    Pathways
    Signaling Pathways (FlyBase)
    Torso Signaling Pathway Core Components -
    The formation of Drosophila embryonic termini is controlled by the localized activation of Torso (tor) receptor tyrosine kinase. The Torso signaling pathway acts via the canonical Ras/Raf/MAP kinase cascade. (Adapted from FBrf0157176.)
    Metabolic Pathways
    External Data
    Linkouts
    KEGG Pathways - Wiring diagrams of molecular interactions, reactions and relations.
    Genomic Location and Detailed Mapping Data
    Chromosome (arm)
    2L
    Recombination map
    2-40
    Cytogenetic map
    Sequence location
    FlyBase Computed Cytological Location
    Cytogenetic map
    Evidence for location
    31B1-31B1
    Limits computationally determined from genome sequence between P{lacW}me31Bk06607 and P{PZ}nmd08774
    Experimentally Determined Cytological Location
    Cytogenetic map
    Notes
    References
    31B-31C
    (determined by in situ hybridisation)
    Experimentally Determined Recombination Data
    Left of (cM)
    Right of (cM)
    Notes
    Stocks and Reagents
    Stocks (12)
    Genomic Clones (22)
    cDNA Clones (0)
     

    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 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
            GenomeRNAi - A database for cell-based and in vivo RNAi phenotypes and reagents
            Antibody Information
            Laboratory Generated Antibodies
             
            Commercially Available Antibodies
             
            Other Information
            Relationship to Other Genes
            Source for database identify of
            Source for database merge of
            Additional comments
            Other Comments

            trk protein is cleaved multiple times in vivo and these proteolytic events are essential for its function.

            Different amounts of tor or trk molecules correlate with the expression of different zygotic genes, implicating changes in the number of activated tor molecules as one of the mechanisms defining differential gene expression.

            trk encodes a protein that resembles spz in several aspects, in particular the sequence suggests that trk is a secreted protein which contains an internal site for proteolytic cleavage. Overall orientation not stated: anon-31BCa+ trk+ anon-31BCb-

            It is proposed that trk encodes an extracellular ligand involved in specifying terminal body pattern and suggests, by analogy with spz, that a cleaved form of trk constitutes the ligand for the tor receptor.

            Distribution of tud protein in mutant embryos has been studied. Maternal genes such as bcd, tor and trk that are necessary for anteroposterior axis formation, but not required for germ cell formation or abdominal segmentation, have no effect on the distribution of tud protein.

            "Splice" phenotype of torNRE dependent on tll, trk and tsl. trk mutation suppresses phenotype of torKr.P.

            The maternal terminal system is necessary to activate tll expression in the terminal caps.

            Mutations in maternal terminal class gene trk interact with RpII140wimp.

            trk plays a role in the specification of the anterior and posterior pole.

            Zygotically active locus involved in the terminal developmental program in the embryo in the embryo.

            Mature follicles are immunologically stained for asymmetric distribution of ecdysteroid-related antigen. During late oogenesis localisation of the antigen changes dramatically suggesting the antigen plays a role in early embryogenesis and, perhaps, in pattern formation.

            Mutations in trk result in a maternal effect phenotype with defects during the early stages of gastrulation and defects in the anteroposterior axis.

            Origin and Etymology
            Discoverer
            Etymology
            Identification
            External Crossreferences and Linkouts ( 28 )
            Sequence Crossreferences
            NCBI Gene - Gene integrates information from a wide range of species. A record may include nomenclature, Reference Sequences (RefSeqs), maps, pathways, variations, phenotypes, and links to genome-, phenotype-, and locus-specific resources worldwide.
            GenBank Nucleotide - A collection of sequences from several sources, including GenBank, RefSeq, TPA, and PDB.
            GenBank Protein - A collection of sequences from several sources, including translations from annotated coding regions in GenBank, RefSeq and TPA, as well as records from SwissProt, PIR, PRF, and PDB.
            RefSeq - A comprehensive, integrated, non-redundant, well-annotated set of reference sequences including genomic, transcript, and protein.
            UniProt/Swiss-Prot - Manually annotated and reviewed records of protein sequence and functional information
            Other crossreferences
            Drosophila Genomics Resource Center - Drosophila Genomics Resource Center (DGRC) cDNA clones
            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
            Eukaryotic Promoter Database - A collection of databases of experimentally validated promoters for selected model organisms.
            FlyAtlas - Adult expression by tissue, using Affymetrix Dros2 array
            FlyAtlas2 - A Drosophila melanogaster expression atlas with RNA-Seq, miRNA-Seq and sex-specific data
            Flygut - An atlas of the Drosophila adult midgut
            GenomeRNAi - A database for cell-based and in vivo RNAi phenotypes and reagents
            InterPro - A database of protein families, domains and functional sites
            KEGG Genes - Molecular building blocks of life in the genomic space.
            MARRVEL_MODEL - MARRVEL (model organism gene)
            modMine - A data warehouse for the modENCODE project
            Linkouts
            BioGRID - A database of protein and genetic interactions.
            DroID - A comprehensive database of gene and protein interactions.
            DRSC - Results frm RNAi screens
            FlyCyc Genes - Genes from a BioCyc PGDB for Dmel
            FlyMine - An integrated database for Drosophila genomics
            Interactive Fly - A cyberspace guide to Drosophila development and metazoan evolution
            KEGG Pathways - Wiring diagrams of molecular interactions, reactions and relations.
            MIST (genetic) - An integrated Molecular Interaction Database
            Synonyms and Secondary IDs (6)
            Datasets (0)
            Study focus (0)
            Experimental Role
            Project
            Project Type
            Title
            References (126)