FB2026_01 , released March 12, 2026
FB2026_01 , released March 12, 2026
Gene: Dmel\mael
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General Information
Symbol
Dmel\mael
Species
D. melanogaster
Name
maelstrom
Annotation Symbol
CG11254
Feature Type
FlyBase ID
FBgn0016034
Gene Model Status
Stock Availability
Gene Summary
Involved both in the piRNA and miRNA metabolic processes. As a component of the meiotic nuage, plays a central role during oogenesis by repressing transposable elements and preventing their mobilization, which is essential for the germline integrity. Repression of transposable elements is mediated via the piRNA metabolic process, which mediates the repression of transposable elements during meiosis by forming complexes composed of piRNAs and Piwi proteins and governs the repression of transposons. As a nuclear component, it is required for proper differentiation in the germline stem cell (GSC) lineage by repressing microRNA-7 (miR-7), thereby acting as an indirect regulator of bag-of-marbles (Bam). Acts by binding to the promoter of miR-7 gene and repressing its expression; miR-7 repression alleviates the Bam repression by miR-7, thereby allowing differentiation in the germline stem cell (GSC) lineage. Indirectly required to position the microtubule organizing center in stage 2-6 oocytes. Involved in repression of long interspersed nuclear elements (LINEs) including HeT-A, I-element, TART and possibly mst40 LINEs; may have a role in production of piwi-interacting RNA (piRNA) (PubMed:17428915). (UniProt, Q9VNS0)
Contribute a Gene Snapshot for this gene.
Key Links
Genomic Location
Cytogenetic map
Sequence location
Recombination map
3-47
RefSeq locus
NT_037436 REGION:22721203..22726234
Sequence
Genomic Maps
Other Genome Views
The following external sites may use different assemblies or annotations than FlyBase.
Function
Gene Ontology (GO) Annotations (28 terms)
Molecular Function (2 terms)
Terms Based on Experimental Evidence (1 term)
CV Term
Evidence
References
Terms Based on Predictions or Assertions (1 term)
CV Term
Evidence
References
inferred from biological aspect of ancestor with PANTHER:PTN000482813
Biological Process (22 terms)
Terms Based on Experimental Evidence (19 terms)
CV Term
Evidence
References
inferred from mutant phenotype
inferred from mutant phenotype
inferred from mutant phenotype
inferred from mutant phenotype
inferred from mutant phenotype
inferred from mutant phenotype
inferred from mutant phenotype
inferred from mutant phenotype
inferred from mutant phenotype
inferred from mutant phenotype
involved_in oogenesis
inferred from mutant phenotype
involved_in piRNA processing
inferred from mutant phenotype
inferred from mutant phenotype
inferred from mutant phenotype
involved_in spermatogenesis
inferred from mutant phenotype
Terms Based on Predictions or Assertions (7 terms)
CV Term
Evidence
References
traceable author statement
traceable author statement
inferred from biological aspect of ancestor with PANTHER:PTN000482813
involved_in piRNA processing
inferred from biological aspect of ancestor with PANTHER:PTN000482813
involved_in spermatogenesis
inferred from biological aspect of ancestor with PANTHER:PTN000482813
Cellular Component (4 terms)
Terms Based on Experimental Evidence (4 terms)
CV Term
Evidence
References
located_in cytoplasm
inferred from direct assay
located_in nucleus
inferred from direct assay
inferred from direct assay
is_active_in P granule
inferred from direct assay
located_in P granule
inferred from direct assay
inferred from direct assay
Terms Based on Predictions or Assertions (2 terms)
CV Term
Evidence
References
is_active_in nucleus
inferred from biological aspect of ancestor with PANTHER:PTN000482813
is_active_in P granule
inferred from biological aspect of ancestor with PANTHER:PTN000482813
Gene Group (FlyBase)
Protein Family (UniProt)
Belongs to the maelstrom family. (Q9VNS0)
Summaries
Protein Function (UniProtKB)
Involved both in the piRNA and miRNA metabolic processes. As a component of the meiotic nuage, plays a central role during oogenesis by repressing transposable elements and preventing their mobilization, which is essential for the germline integrity. Repression of transposable elements is mediated via the piRNA metabolic process, which mediates the repression of transposable elements during meiosis by forming complexes composed of piRNAs and Piwi proteins and governs the repression of transposons. As a nuclear component, it is required for proper differentiation in the germline stem cell (GSC) lineage by repressing microRNA-7 (miR-7), thereby acting as an indirect regulator of bag-of-marbles (Bam). Acts by binding to the promoter of miR-7 gene and repressing its expression; miR-7 repression alleviates the Bam repression by miR-7, thereby allowing differentiation in the germline stem cell (GSC) lineage. Indirectly required to position the microtubule organizing center in stage 2-6 oocytes. Involved in repression of long interspersed nuclear elements (LINEs) including HeT-A, I-element, TART and possibly mst40 LINEs; may have a role in production of piwi-interacting RNA (piRNA) (PubMed:17428915).
(UniProt, Q9VNS0)
Summary (Interactive Fly)

HMG box protein - spindle class protein - potential regulator of RNA processing or subcellular localization - essential for piRNA-mediated transcriptional transposon silencing - coordinates microtubule organization during Drosophila oogenesis through interaction with components of the microtubule-organizing center

Gene Model and Products
Number of Transcripts
4
Number of Unique Polypeptides
2

Please see the JBrowse view of Dmel\mael 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 Q9VNS0)

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
PDB - An information portal to biological macromolecular structures
Comments on Gene Model

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

Gene model reviewed during 5.43

Gene model reviewed during 5.45

Antisense UTR:

Gene model reviewed during 6.02

Transcript Data
Annotated Transcripts
Name
FlyBase ID
RefSeq ID
Length (nt)
Assoc. CDS (aa)
FBtr0089633
1759
459
FBtr0089632
1830
459
FBtr0089631
1839
462
FBtr0347062
2143
459
Additional Transcript Data and Comments
Reported size (kB)

1.8 (northern blot)

Comments
External Data
Crossreferences
Polypeptide Data
Annotated Polypeptides
Name
FlyBase ID
Predicted MW (kDa)
Length (aa)
Theoretical pI
UniProt
RefSeq ID
GenBank
FBpp0088576
51.6
459
8.30
FBpp0088575
51.6
459
8.30
FBpp0088574
52.0
462
8.30
FBpp0312456
51.6
459
8.30
Polypeptides with Identical Sequences

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

459 aa isoforms: mael-PA, mael-PB, mael-PD
Additional Polypeptide Data and Comments
Reported size (kDa)

459 (aa); 48 (kD observed)

Comments
External Data
Crossreferences
InterPro - A database of protein families, domains and functional sites
PDB - An information portal to biological macromolecular structures
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\mael 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).

1.57

Transcript Expression
expression microarray
Stage
Tissue/Position (including subcellular localization)
Reference
in situ
Stage
Tissue/Position (including subcellular localization)
Reference
organism

Comment: maternally deposited

Additional Descriptive Data

mael transcript is expressed at a weak to moderate level in the CNS of late stage embryos. mael transcript is also expressed in dimm-positive neurons in adults.

Marker for
 
Subcellular Localization
CV Term
Polypeptide Expression
immunolocalization
Stage
Tissue/Position (including subcellular localization)
Reference
Additional Descriptive Data

During oogenesis, mael protein is detected in a punctate pattern in germ line cells throughout the germarium, including those in germarium region 1. Expression is uniform in nurse cells and oocytes in early egg chambers, but by stage S5, it is strongest around the periphery of cells. Protein accumulation decreases in stages S5 and S6, especially in the oocyte. No mael protein is detected after stage S8.

Marker for
 
Subcellular Localization
CV Term
Evidence
References
located_in cytoplasm
inferred from direct assay
located_in nucleus
inferred from direct assay
inferred from direct assay
is_active_in P granule
inferred from direct assay
located_in P granule
inferred from direct assay
inferred from direct assay
Expression Deduced from Reporters
High-Throughput Expression Data
Associated Tools

JBrowse - Visual display of RNA-Seq signals

View Dmel\mael 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) 4-6
  • Stages(s) 7-8
  • Stages(s) 9-10
  • Stages(s) 11-12
  • Stages(s) 13-16
Alleles, Insertions, Transgenic Constructs, and Aberrations
Classical and Insertion Alleles ( 11 )
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 mael
Transgenic constructs containing regulatory region of mael
Aberrations (Deficiencies and Duplications) ( 1 )
Inferred from experimentation ( 1 )
Inferred from location ( 5 )
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
Sterility
Allele
Other Phenotypes
Allele
Phenotype manifest in
Allele
microtubule & oocyte
oocyte & centriole (with Df(3L)79E-F)
oocyte & microtubule
oocyte & microtubule organizing center (with Df(3L)79E-F)
Orthologs
Human Orthologs (via DIOPT v9.1)
Species\Gene Symbol
Score
Best Score
Best Reverse Score
Alignment
Complementation?
Transgene?
Homo sapiens (Human) (1)
12 of 14
Yes
Yes
Model Organism Orthologs (via DIOPT v9.1)
Species\Gene Symbol
Score
Best Score
Best Reverse Score
Alignment
Complementation?
Transgene?
Rattus norvegicus (Norway rat) (1)
13 of 14
Yes
Yes
Mus musculus (laboratory mouse) (1)
12 of 14
Yes
Yes
Xenopus tropicalis (Western clawed frog) (2)
10 of 13
Yes
Yes
1 of 13
No
Yes
Danio rerio (Zebrafish) (0)
Caenorhabditis elegans (Nematode, roundworm) (0)
Anopheles gambiae (African malaria mosquito) (1)
12 of 12
Yes
Yes
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:mael. Refer to their site for version information.
Paralogs
Paralogs (via DIOPT v9.1)
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

    Please see the Physical Interaction reports below for full details
    protein-protein
    Physical Interaction
    Assay
    References
    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
    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
    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
    Sequence location
    FlyBase Computed Cytological Location
    Cytogenetic map
    Evidence for location
    80A1-80A1
    Limits computationally determined from genome sequence between P{lacW}l(3)j1B10j1B10 and P{lacW}l(3)j2C4j2C4
    Experimentally Determined Cytological Location
    Cytogenetic map
    Notes
    References
    Experimentally Determined Recombination Data
    Location
    Left of (cM)
    Right of (cM)
    Notes
    Stocks and Reagents
    Stocks (10)
    Genomic Clones (16)
     

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

    cDNA Clones (45)
     

    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)
    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

        mael is required for proper differentiation in the germline stem cell lineage in males.

        mael is required in the germline for proper reorientation of the oocyte cytoskeleton in response to signalling from the surrounding follicular epithelium.

        Mutations in mael transform posterior follicle cells into anterior fates.

        mael acts in the germline after follicle cell determination to organise the oocyte cytoskeleton.

        mael function is required in the germline for correct posterior localisation of a variety of transcripts in early oocytes, including grk mRNA. Posterior localisation of grk mRNA in the early oocyte is essential for proper A/P axis formation.

        Mutations reveal a novel step in mRNA localisation within the oocyte. Mutants disrupt the normal assymetric distribution of markers along the A/P axis and they disrupt the microtubule-dependent migration of the oocyte nucleus.

        Required for the localization of morphogens and for the correct formation of the cytoskeleton in oocytes.

        Relationship to Other Genes
        Source for database merge of
        Additional comments
        Nomenclature History
        Source for database identify of

        Source for identity of: mael CG11254

        Nomenclature comments
        Etymology
        Synonyms and Secondary IDs (7)
        Reported As
        Symbol Synonym
        Secondary FlyBase IDs
          Datasets (0)
          Study focus (0)
          Experimental Role
          Project
          Project Type
          Title
          Study result (0)
          Result
          Result Type
          Title
          External Crossreferences and Linkouts ( 52 )
          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
          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
          FlyMine - An integrated database for Drosophila genomics
          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)
          PDB - An information portal to biological macromolecular structures
          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)
          Interactive Fly - A cyberspace guide to Drosophila development and metazoan evolution
          MIST (genetic) - An integrated Molecular Interaction Database
          MIST (protein-protein) - An integrated Molecular Interaction Database
          References (145)