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General Information
Symbol
Dmel\fzo
Species
D. melanogaster
Name
fuzzy onions
Annotation Symbol
CG4568
Feature Type
FlyBase ID
FBgn0011596
Gene Model Status
Stock Availability
Gene Snapshot
fuzzy onions (fzo) encodes an evolutionarily conserved transmembrane Dynamin-type GTPase and founder member of the mitofusin class of proteins. It is required for proper fusion of mitochondria during spermatid differentiation to form the Nebenkern mitochondrial formation. [Date last reviewed: 2019-03-07]
Key Links
Genomic Location
Cytogenetic map
Sequence location
3R:23,201,644..23,204,034 [-]
Recombination map

3-78

RefSeq locus
NT_033777 REGION:23201644..23204034
Sequence
Other Genome Views
The following external sites may use different assemblies or annotations than FlyBase.
Function
GO Summary Ribbons
Gene Group (FlyBase)
Protein Family (UniProt)
Belongs to the TRAFAC class dynamin-like GTPase superfamily. Dynamin/Fzo/YdjA family. Mitofusin subfamily. (O18412)
Molecular Function (GO)
[Detailed GO annotations]
Experimental Evidence
-
Predictions / Assertions
Summaries
Gene Group (FlyBase)
MITOFUSINS -
Mitofusins are GTPases of the outer mitochondrial membrane that are essential for the controlled fusion of mitochondrial membranes. (Adapted from FBrf0151407).
Protein Function (UniProtKB)
Essential transmembrane GTPase, which mediates mitochondrial fusion during spermatogenesis. In early spermatocytes, fusion of mitochondria give rise to two organelles named Nebenkern and constitutes an important step in mitochondria morphology, which is balanced between fusion and fission. Essential for fertility.
(UniProt, O18412)
Gene Model and Products
Number of Transcripts
1
Number of Unique Polypeptides
1

Please see the GBrowse view of Dmel\fzo or the JBrowse view of Dmel\fzo 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 5.47

Sequence Ontology: Class of Gene
Transcript Data
Annotated Transcripts
Name
FlyBase ID
RefSeq ID
Length (nt)
Assoc. CDS (aa)
FBtr0084399
2391
718
Additional Transcript Data and Comments
Reported size (kB)

2.399 (longest cDNA)

Comments
External Data
Crossreferences
Polypeptide Data
Annotated Polypeptides
Name
FlyBase ID
Predicted MW (kDa)
Length (aa)
Theoretical pI
RefSeq ID
GenBank
FBpp0083791
81.6
718
6.06
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
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\fzo using the Feature Mapper tool.

External Data
Crossreferences
Eukaryotic Promoter Database - A collection of databases of experimentally validated promoters for selected model organisms.
Linkouts
Gene Ontology (10 terms)
Molecular Function (2 terms)
Terms Based on Experimental Evidence (0 terms)
Terms Based on Predictions or Assertions (2 terms)
CV Term
Evidence
References
inferred from electronic annotation with InterPro:IPR030381
(assigned by InterPro )
inferred from biological aspect of ancestor with PANTHER:PTN000049197
(assigned by GO_Central )
inferred from sequence or structural similarity
Biological Process (5 terms)
Terms Based on Experimental Evidence (3 terms)
CV Term
Evidence
References
inferred from mutant phenotype
inferred from mutant phenotype
inferred from mutant phenotype
Terms Based on Predictions or Assertions (4 terms)
CV Term
Evidence
References
inferred from biological aspect of ancestor with PANTHER:PTN000825684
(assigned by GO_Central )
traceable author statement
inferred from biological aspect of ancestor with PANTHER:PTN000825684
(assigned by GO_Central )
traceable author statement
traceable author statement
Cellular Component (3 terms)
Terms Based on Experimental Evidence (1 term)
CV Term
Evidence
References
Terms Based on Predictions or Assertions (2 terms)
CV Term
Evidence
References
inferred from electronic annotation with InterPro:IPR006884
(assigned by InterPro )
traceable author statement
inferred from biological aspect of ancestor with PANTHER:PTN000825684
(assigned by GO_Central )
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
northern blot
Stage
Tissue/Position (including subcellular localization)
Reference
organism

Comment: not observed in adult females or embryos

Additional Descriptive Data

fzo is observed in primary spermatocytes, but is absent in early spermatid.

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

fzo protein is detected at the end of male meiosis and in early stage spermatids when mitochondrial fusion occurs.

fzo protein is associated with mitochondria in spermatids during a narrow developmental window. It is first detected in the last stages of meiosis II. In postmeiotic haploid spermatids, it is associated with aggregating mitochondria and is present at the highest levels on onion stage Nebenkerns. It is detected at lower levels on early elongation stage mitochondria.

Marker for
 
Subcellular Localization
CV Term
Evidence
References
Expression Deduced from Reporters
High-Throughput Expression Data
Associated Tools

GBrowse - Visual display of RNA-Seq signals

View Dmel\fzo 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
BDGP expression data - Patterns of gene expression in Drosophila embryogenesis
FLIGHT - Cell culture data for RNAi and other high-throughput technologies
FlyAtlas - Adult expression by tissue, using Affymetrix Dros2 array
Flygut - An atlas of the Drosophila adult midgut
Images
Alleles, Insertions, and Transgenic Constructs
Classical and Insertion Alleles ( 4 )
For All Classical and Insertion Alleles Show
 
Other relevant insertions
Transgenic Constructs ( 6 )
For All Alleles Carried on Transgenic Constructs Show
Transgenic constructs containing/affecting coding region of fzo
Transgenic constructs containing regulatory region of fzo
Deletions and Duplications ( 5 )
Phenotypes
For more details about a specific phenotype click on the relevant allele symbol.
Lethality
Allele
Sterility
Allele
Phenotype manifest in
Allele
onion stage spermatid & mitochondrion
spermatid & mitochondrion
Orthologs
Human Orthologs (via DIOPT v7.1)
Homo sapiens (Human) (9)
Species\Gene Symbol
Score
Best Score
Best Reverse Score
Alignment
Complementation?
Transgene?
7 of 15
Yes
No
 
6 of 15
No
No
 
1 of 15
No
No
1 of 15
No
No
 
1 of 15
No
No
 
1 of 15
No
No
1 of 15
No
No
1 of 15
No
No
1 of 15
No
No
Model Organism Orthologs (via DIOPT v7.1)
Mus musculus (laboratory mouse) (7)
Species\Gene Symbol
Score
Best Score
Best Reverse Score
Alignment
Complementation?
Transgene?
7 of 15
Yes
No
5 of 15
No
No
1 of 15
No
No
1 of 15
No
No
1 of 15
No
No
1 of 15
No
No
1 of 15
No
No
Rattus norvegicus (Norway rat) (7)
5 of 13
Yes
No
5 of 13
Yes
No
3 of 13
No
No
1 of 13
No
No
1 of 13
No
No
1 of 13
No
No
1 of 13
No
No
Xenopus tropicalis (Western clawed frog) (7)
5 of 12
Yes
No
5 of 12
Yes
No
1 of 12
No
No
1 of 12
No
No
1 of 12
No
No
1 of 12
No
No
1 of 12
No
No
Danio rerio (Zebrafish) (18)
7 of 15
Yes
Yes
6 of 15
No
No
5 of 15
No
No
1 of 15
No
No
1 of 15
No
No
1 of 15
No
No
1 of 15
No
No
1 of 15
No
No
1 of 15
No
No
1 of 15
No
No
1 of 15
No
No
1 of 15
No
No
1 of 15
No
No
1 of 15
No
No
1 of 15
No
No
1 of 15
No
No
Caenorhabditis elegans (Nematode, roundworm) (3)
7 of 15
Yes
No
1 of 15
No
No
1 of 15
No
No
Arabidopsis thaliana (thale-cress) (1)
1 of 9
Yes
Yes
Saccharomyces cerevisiae (Brewer's yeast) (4)
6 of 15
Yes
Yes
1 of 15
No
No
1 of 15
No
No
1 of 15
No
No
Schizosaccharomyces pombe (Fission yeast) (1)
6 of 12
Yes
Yes
Orthologs in Drosophila Species (via OrthoDB v9.1) ( EOG091903QV )
Organism
Common Name
Gene
AAA Syntenic Ortholog
Multiple Dmel Genes in this Orthologous Group
Drosophila simulans
Drosophila erecta
Drosophila yakuba
Drosophila persimilis
Drosophila virilis
Drosophila mojavensis
Orthologs in non-Drosophila Dipterans (via OrthoDB v9.1) ( None identified )
No non-Drosophilid orthologies identified
Orthologs in non-Dipteran Insects (via OrthoDB v9.1) ( None identified )
No non-Dipteran orthologies identified
Orthologs in non-Insect Arthropods (via OrthoDB v9.1) ( None identified )
No non-Insect Arthropod orthologies identified
Orthologs in non-Arthropod Metazoa (via OrthoDB v9.1) ( EOG091G02ES )
Organism
Common Name
Gene
Multiple Dmel Genes in this Orthologous Group
Strongylocentrotus purpuratus
Purple sea urchin
Strongylocentrotus purpuratus
Purple sea urchin
Ciona intestinalis
Vase tunicate
Gallus gallus
Domestic chicken
Gallus gallus
Domestic chicken
Paralogs
Paralogs (via DIOPT v7.1)
Drosophila melanogaster (Fruit fly) (4)
6 of 10
1 of 10
1 of 10
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 ( 3 )
    Modifiers Based on Experimental Evidence ( 0 )
    Allele
    Disease
    Interaction
    References
    Disease Associations of Human Orthologs (via DIOPT v7.1 and OMIM)
    Note that ortholog calls supported by only 1 or 2 algorithms (DIOPT score < 3) are not shown.
    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
    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.
    InterologFinder - Protein-protein interactions (PPI) from both known and predicted PPI data sets.
    Pathways
    Signaling Pathways (FlyBase)
    Metabolic Pathways
    External Data
    Linkouts
    KEGG Pathways - Wiring diagrams of molecular interactions, reactions and relations.
    Reactome - An open-source, open access, manually curated and peer-reviewed pathway database.
    Genomic Location and Detailed Mapping Data
    Chromosome (arm)
    3R
    Recombination map

    3-78

    Cytogenetic map
    Sequence location
    3R:23,201,644..23,204,034 [-]
    FlyBase Computed Cytological Location
    Cytogenetic map
    Evidence for location
    94E6-94E6
    Limits computationally determined from genome sequence between P{PZ}cnc03921 and P{PZ}l(3)0690606906
    Experimentally Determined Cytological Location
    Cytogenetic map
    Notes
    References
    94E5-94E11
    94E3-95A3
    (determined by in situ hybridisation)
    Experimentally Determined Recombination Data
    Location
    Right of (cM)
    Notes
    Stocks and Reagents
    Stocks (6)
    Genomic Clones (12)
     

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

    cDNA Clones (5)
     

    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 sequences
    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

      Source for merge of: fzo anon-WO0125274.1 anon-WO0125274.25 anon-WO0125274.26

      Additional comments

      Source for merge of fzo anon-WO0125274.1 anon-WO0125274.25 anon-WO0125274.26 was sequence comparison ( date:051113 ).

      Other Comments

      Area matching Drosophila Fzo gene, Acc. No. U95821.

      fzo has been cloned and characterised. fzo encodes a predicted transmembrane GTPase that is required for mitochondrial fusion during spermatogenesis.

      At the round spermatid stage all mitochondria in each haploid spermatid fuse into two large derivatives that interweave to form the nebenkern, in fzo mutants the mitochondria aggregate but fail to fuse. The defect is specific to fusion as each unfused mitochondrion elongates normally.

      Origin and Etymology
      Discoverer
      Etymology
      Identification
      External Crossreferences and Linkouts ( 37 )
      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
      BDGP expression data - Patterns of gene expression in Drosophila embryogenesis
      Drosophila Genomics Resource Center - Drosophila Genomics Resource Center (DGRC) cDNA clones
      Eukaryotic Promoter Database - A collection of databases of experimentally validated promoters for selected model organisms.
      Flygut - An atlas of the Drosophila adult midgut
      GenomeRNAi - A database for cell-based and in vivo RNAi phenotypes and reagents
      KEGG Genes - Molecular building blocks of life in the genomic space.
      modMine - A data warehouse for the modENCODE project
      Linkouts
      BioGRID - A database of protein and genetic interactions.
      DPiM - Drosophila Protein interaction map
      DroID - A comprehensive database of gene and protein interactions.
      DRSC - Results frm RNAi screens
      FLIGHT - Cell culture data for RNAi and other high-throughput technologies
      FlyAtlas - Adult expression by tissue, using Affymetrix Dros2 array
      FlyCyc Genes - Genes from a BioCyc PGDB for Dmel
      FlyMine - An integrated database for Drosophila genomics
      InterologFinder - Protein-protein interactions (PPI) from both known and predicted PPI data sets.
      KEGG Pathways - Wiring diagrams of molecular interactions, reactions and relations.
      Reactome - An open-source, open access, manually curated and peer-reviewed pathway database.
      Synonyms and Secondary IDs (9)
      Datasets (0)
      Study focus (0)
      Experimental Role
      Project
      Project Type
      Title
      References (84)