FB2025_05 , released December 11, 2025
Gene: Dmel\serp
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General Information
Symbol
Dmel\serp
Species
D. melanogaster
Name
serpentine
Annotation Symbol
CG32209
Feature Type
protein_coding_gene
FlyBase ID
FBgn0260653
Gene Model Status
Current
Stock Availability
15 publicly available
Enzyme Name (EC)
chitin deacetylase (3.5.1.41)
Gene Summary
serpentine (serp) encodes a putative chitin deacetylase. It is expressed by the epidermal and tracheal cells and is secreted into the apical extracellular space. Its activity maintains the strength of cuticles and restricts tracheal tube length. [Date last reviewed: 2019-03-14] (FlyBase Gene Snapshot)
All Summaries
Also Known As

l(3)76BDk

Key Links
Genomic Location
Cytogenetic map
76C2-76C2
Sequence location
Recombination map
3-46
RefSeq locus
NT_037436 REGION:19700977..19708015
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 (17 terms)
Molecular Function (3 terms)
Terms Based on Experimental Evidence (2 terms)
CV Term
Evidence
References
enables chitin binding
inferred from mutant phenotype
(Wang et al., 2006)
enables chitin deacetylase activity
inferred from mutant phenotype
(Zhang et al., 2019, Wang et al., 2006)
Terms Based on Predictions or Assertions (3 terms)
CV Term
Evidence
References
enables chitin binding
inferred from electronic annotation with InterPro:IPR002557, InterPro:IPR036508
(InterPro Project Members, 2004-)
inferred from biological aspect of ancestor with PANTHER:PTN000829569
(GO Reference Genome Project, 2011-)
enables chitin deacetylase activity
inferred from biological aspect of ancestor with PANTHER:PTN000829569
(GO Reference Genome Project, 2011-)
enables hydrolase activity, acting on carbon-nitrogen (but not peptide) bonds
inferred from electronic annotation with InterPro:IPR002509
(InterPro Project Members, 2004-)
Biological Process (7 terms)
Terms Based on Experimental Evidence (6 terms)
CV Term
Evidence
References
involved_in adult chitin-based cuticle development
inferred from mutant phenotype
(Zhang et al., 2019)
involved_in chitin metabolic process
inferred from mutant phenotype
(Zhang et al., 2019)
involved_in chitin-based cuticle development
inferred from mutant phenotype
(Luschnig et al., 2006)
involved_in larval chitin-based cuticle development
inferred from mutant phenotype
(Pesch et al., 2015)
involved_in open tracheal system development
inferred from mutant phenotype
(Luschnig et al., 2006, Wang et al., 2006)
involved_in regulation of tube length, open tracheal system
inferred from mutant phenotype
(Luschnig et al., 2006, Wang et al., 2006)
Terms Based on Predictions or Assertions (4 terms)
CV Term
Evidence
References
involved_in adult chitin-based cuticle development
inferred from biological aspect of ancestor with PANTHER:PTN000829569
(GO Reference Genome Project, 2011-)
involved_in carbohydrate metabolic process
inferred from electronic annotation with InterPro:IPR002509, InterPro:IPR011330
(InterPro Project Members, 2004-)
involved_in larval chitin-based cuticle development
inferred from biological aspect of ancestor with PANTHER:PTN000829569
(GO Reference Genome Project, 2011-)
involved_in regulation of tube length, open tracheal system
inferred from biological aspect of ancestor with PANTHER:PTN000829569
(GO Reference Genome Project, 2011-)
Cellular Component (7 terms)
Terms Based on Experimental Evidence (7 terms)
CV Term
Evidence
References
located_in basement membrane
inferred from direct assay
(Dong et al., 2014)
located_in cell surface
inferred from direct assay
(Pesch et al., 2015)
located_in chitin-based extracellular matrix
inferred from direct assay
(Pesch et al., 2015, Petkau et al., 2012, Luschnig et al., 2006)
located_in cytoplasm
inferred from direct assay
(Kakihara et al., 2008)
located_in extracellular region
inferred from direct assay
(Wang et al., 2006)
located_in extracellular space
inferred from direct assay
(Dong et al., 2014)
located_in late endosome
inferred from direct assay
(Dong et al., 2013)
Terms Based on Predictions or Assertions (1 term)
CV Term
Evidence
References
located_in extracellular region
inferred from electronic annotation with InterPro:IPR002557
(InterPro Project Members, 2004-)
Gene Group (FlyBase)
Protein Family (UniProt)
-
Protein Signatures (InterPro)
Catalytic Activity (EC/Rhea)
chitin deacetylase activity
[(1->4)-N-acetyl-beta-D-glucosaminyl](n) + n H2O = chitosan + n acetate (3.5.1.41)
RHEA 10464:
Summaries
Gene Snapshot
serpentine (serp) encodes a putative chitin deacetylase. It is expressed by the epidermal and tracheal cells and is secreted into the apical extracellular space. Its activity maintains the strength of cuticles and restricts tracheal tube length. [Date last reviewed: 2019-03-14]
Gene Group (FlyBase)
CHITIN BINDING DOMAIN-CONTAINING PROTEINS -
Chitin binding domains are found in certain classes of chitin binding proteins and chitin-active enzymes. (Adapted from FBrf0108362.)
CHITIN DEACETYLASES -
Chitin deacetylases are secreted enzymes that deacetylate chitin to chitosan. (Adapted from FBrf0204376.)
Summary (Interactive Fly)

secreted polysaccharide deacetylases - converts chitin to chitosan - required to assemble cable-like extracellular matrix and restrict tracheal tube elongation

Gene Model and Products
Number of Transcripts
2
Number of Unique Polypeptides
1

Please see the JBrowse view of Dmel\serp 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 Q9VW34)

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

Low-frequency RNA-Seq exon junction(s) not annotated.

Gene model reviewed during 5.46

Transcript Data
Annotated Transcripts
Name
FlyBase ID
RefSeq ID
Length (nt)
Assoc. CDS (aa)
serp-RB
FBtr0074953
NM_168811
2541
541
serp-RC
FBtr0333862
NM_001275133
2226
541
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
serp-PB
FBpp0074721
61.6
541
4.71
Q9VW34
NP_730444
AAF49119
serp-PC
FBpp0305995
61.6
541
4.71
Q9VW34
NP_001262062
AGB94755
Polypeptides with Identical Sequences

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

541 aa isoforms: serp-PB, serp-PC
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
Mapped Features

Click to get a list of regulatory features (enhancers, TFBS, etc.) and gene disruptions (point mutations, indels, etc.) within or overlapping Dmel\serp 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).

-0.58

Transcript Expression
Polypeptide Expression
immunolocalization
Stage
Tissue/Position (including subcellular localization)
Reference
embryonic stage 13
embryonic/larval tracheal section
(Dong et al., 2013)
embryonic stage 14 -- 16
tracheal lumen
(Dong et al., 2013)
Additional Descriptive Data

By stage 14, serp produced in tracheal cells is released into the lumen at the onset of the secretion that initiates tube diameter expansion.

(Dong et al., 2013)
Marker for
 
Subcellular Localization
CV Term
Evidence
References
located_in basement membrane
inferred from direct assay
(Dong et al., 2014)
located_in cell surface
inferred from direct assay
(Pesch et al., 2015)
located_in chitin-based extracellular matrix
inferred from direct assay
(Pesch et al., 2015, Petkau et al., 2012, Luschnig et al., 2006)
located_in cytoplasm
inferred from direct assay
(Kakihara et al., 2008)
located_in extracellular region
inferred from direct assay
(Wang et al., 2006)
located_in extracellular space
inferred from direct assay
(Dong et al., 2014)
located_in late endosome
inferred from direct assay
(Dong et al., 2013)
Expression Deduced from Reporters
High-Throughput Expression Data
Associated Tools

JBrowse - Visual display of RNA-Seq signals

View Dmel\serp 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
FlyBase Wiki
Image Based Resources
Alleles, Insertions, Transgenic Constructs, and Aberrations
Classical and Insertion Alleles ( 8 )
For All Classical and Insertion Alleles Show
 
Other relevant insertions
Transgenic Constructs ( 18 )
For All Alleles Carried on Transgenic Constructs Show
Transgenic constructs containing/affecting coding region of serp
Transgenic constructs containing regulatory region of serp
Aberrations (Deficiencies and Duplications) ( 27 )
Variants
Variant Molecular Consequences
Alleles Representing Disease-Implicated Variants
Phenotypes
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) (2)
Cele\lgx-1
6 of 14
Yes
No
Cele\Y47D3B.6
1 of 14
No
Yes
Anopheles gambiae (African malaria mosquito) (5)
Agam\AgaP_AGAP011936
12 of 12
Yes
Yes
Agam\AgaP_AGAP011937
6 of 12
No
No
Agam\AgaP_AGAP000359
4 of 12
No
No
Agam\AgaP_AGAP008123
4 of 12
No
No
Agam\AgaP_AGAP008512
3 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:serp. 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) (5)
ChLD3
7 of 13
verm
7 of 13
Cda4
6 of 13
Cda5
6 of 13
Cda9
4 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
    serp - obst-A
    pull down, western blot
    (Petkau et al., 2012)
    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
    serp
    suppressible
    emp
    (Pinheiro et al., 2023)
    serp
    enhanceable
    verm
    (Luschnig et al., 2006)
    Starting gene(s)
    Interaction type
    Interacting gene(s)
    Reference
    verm
    enhanceable
    serp
    (Luschnig et al., 2006)
    External Data
    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
    FlyCyc Pathways - Pathways from a BioCyc PGDB for Dmel
    External Data
    Linkouts
    Class of Gene
    Genomic Location and Detailed Mapping Data
    Chromosome (arm)
    3L
    Recombination map
    3-46
    Cytogenetic map
    76C2-76C2
    Sequence location
    FlyBase Computed Cytological Location
    Cytogenetic map
    Evidence for location
    76C2-76C2
    Limits computationally determined from genome sequence between P{lacW}l(3)L3809L3809 and P{lacW}l(3)L1243L1243&P{lacW}Mi-2j3D4
    Experimentally Determined Cytological Location
    Cytogenetic map
    Notes
    References
    Experimentally Determined Recombination Data
    Location

    3-46

    (FlyBase, 2016)

    3-43.1

    (Comeron et al., 2012)
    Left of (cM)
    Right of (cM)
    Notes
    Stocks and Reagents
    Stocks (15)
    Genomic Clones (17)
     

    Please Note FlyBase no longer curates genomic clone accessions so this list may not be complete

    cDNA Clones (24)
     

    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
     
    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: serp l(3)76BDk

        (Cook, 2008.12.1)

        Source for merge of: CG8747 CG8748

        (FlyBase Genome Annotators, 2002-2003)
        Additional comments

        Annotations CG8747 and CG8748 merged as CG32209 in release 3 of the genome annotation.

        (FlyBase Genome Annotators, 2002-2003)
        Nomenclature History
        Source for database identify of

        Source for identity of: serp CG32209

        (Wang et al., 2006)
        Nomenclature comments
        Etymology
        Synonyms and Secondary IDs (9)
        Reported As
        Symbol Synonym
        CG32209
        (Zhang et al., 2019, Parisi et al., 2010, Lebo et al., 2009, Perkins et al., 2009, Venkatachalam et al., 2008, Stahl et al., 2007, Tomancak et al., 2007, Luschnig et al., 2006, Wang et al., 2006)
        CG8747
        (Michaut et al., 2003)
        CG8748
        (Ibrahim et al., 2013, Michaut et al., 2003, Zinke et al., 2002)
        DmCDA1
        (Dixit et al., 2008)
        Serp
        (Li et al., 2024, Drees et al., 2023, Li et al., 2022, Camelo and Luschnig, 2021, Rice et al., 2021, Königsmann et al., 2020, Wang et al., 2020, Lattner et al., 2019, McSharry and Beitel, 2019, Skouloudaki et al., 2019, Chandran et al., 2018, Kato et al., 2016, Dong and Hayashi, 2015, Hildebrandt et al., 2015, Bätz et al., 2014, Chandran et al., 2014, Dong et al., 2014, Jaspers et al., 2014, Dong et al., 2013, Dong et al., 2013, Zuo et al., 2013, Armbruster and Luschnig, 2012, Ile et al., 2012, Forster et al., 2010, Forster et al., 2010, Nelson et al., 2010, Norum et al., 2010, Tajiri et al., 2010, Massarwa et al., 2009, Swanson et al., 2009, Grieder et al., 2008, Wu et al., 2007, Swanson and Beitel, 2006)
        l(3)76BDk
        (Cooper et al., 2010, Cook, 2008.12.1)
        serp
        (Pignataro et al., 2024, Pinheiro et al., 2023, Zhang et al., 2023, Pasquier and Robichon, 2022, Cho et al., 2020, Kennison, 2020.10.22, Parra and Johnston, 2020, Rice et al., 2020, Statzer and Ewald, 2020, Hayashi and Dong, 2017, Yao et al., 2017, Toggweiler et al., 2016, Dong et al., 2014, Förster and Luschnig, 2012, Gangishetti et al., 2012, Petkau et al., 2012, Chung et al., 2011, Cooper et al., 2010, Laprise et al., 2010, Cook, 2008.12.1, Kakihara et al., 2008, Behr et al., 2007, Luschnig et al., 2006, Swanson and Beitel, 2006)
        Name Synonyms
        CG32209
        Serpentine
        (Chandran et al., 2014, Dong et al., 2014, Nelson et al., 2010, Grieder et al., 2008, Kakihara et al., 2008, Luschnig et al., 2006, Swanson and Beitel, 2006)
        l(3)76BDk
        serpentine
        (Hayashi and Dong, 2017, Cooper et al., 2010, Laprise et al., 2010, Lebo et al., 2009, Dixit et al., 2008, Behr et al., 2007)
        Secondary FlyBase IDs
        • FBgn0052209
        • FBgn0036902
        • FBgn0036903
        • FBgn0084276
        Datasets (0)
        Study focus (0)
        Experimental Role
        Project
        Project Type
        Title
        Study result (0)
        Result
        Result Type
        Title
        External Crossreferences and Linkouts ( 45 )
        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/TrEMBL - Automatically annotated and unreviewed 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
        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)
        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
        FlyCyc Pathways - Pathways 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)
        Interactive Fly - A cyberspace guide to Drosophila development and metazoan evolution
        MIST (protein-protein) - An integrated Molecular Interaction Database
        References (106)