svb, shavenbaby, shaven baby, ovo/svb, ovoD
zinc finger transcription factor - involved in ovarian maturation, sex determination, segment polarity
Please see the JBrowse view of Dmel\ovo for information on other features
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AlphaFold produces a per-residue confidence score (pLDDT) between 0 and 100. Some regions with low pLDDT may be unstructured in isolation.
Gene model reviewed during 5.43
Low-frequency RNA-Seq exon junction(s) not annotated.
Annotated transcripts do not represent all possible combinations of alternative exons and/or alternative promoters.
Gene model reviewed during 5.52
Gene model reviewed during 6.61
5.0 (northern blot)
5.0, 4.8 (northern blot)
1028, 850 (aa); 110.6, 92 (kD predicted)
131 (kD predicted)
The ovo protein is at least 1209 amino acids
long. In addition to four zinc finger repeats, the protein contains
homopolymeric runs of several different amino acids, and has an extremely
hydrophilic amino acid profile.
Only 3 of the 4 C2H2-type zinc-fingers are required for DNA-binding. Based on its marked lack of evolutionary conservation, the fourth zinc-finger is unlikely to be required.
Click to get a list of regulatory features (enhancers, TFBS, etc.) and gene disruptions (point mutations, indels, etc.) within or overlapping Dmel\ovo using the Feature Mapper tool.
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).
Comment: maternally deposited
Comment: late embryonic stage 12
Comment: late embryonic stage 13
Comment: late embryonic stage 13
Comment: late embryonic stage 13
Comment: more pronounced in stout bristle rows than in fine hair rows
At embryonic stage 9, ovo is expressed in the six rows of cells in each segment that will go on to form the six rows of denticles.
The ovo protein is detected in germ cell nuclei, and may be associated with chromatin.
JBrowse - Visual display of RNA-Seq signals
View Dmel\ovo in JBrowse
Please Note FlyBase no longer curates genomic clone accessions so this list may not be complete
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.
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.
Expression is enriched in embryonic gonads.
ovo is necessary and sufficient for cells to grow F-actin based extensions.
ovo is a key selector gene that, cell autonomously, directs cytoskeletal modifications producing the denticle.
High ovo+ copy number is not sufficient for overt development of XY germ cells. The absence of ovo+ in XX germ cells results in altered sex determination and cell viability, but increased ovo+ activity in XY germ cells is insufficient to impair germline viability and is probably insufficient to alter sexual identity.
A method that allows the efficient recovery of female germline mosaics for mutations localised n the autosomes has been developed using P{ovoD1-18} P{FRT(whs)} P{hsFLP}.
The dominant-negative effects of the ovoD mutations are likely to arise from the expression of novel protein isoforms, starting during germline cell differentiation.
Female germ cells require zygotic ovo function for survival mainly during the second larval, third larval and pupal stages.
otu and ovo are required cell autonomously in the female germline for germ cell proliferation and differentiation. XY germ cells do not require otu when developing in testes, but become dependent on otu function for proliferation when placed in an ovary. The requirement for ovo is dependent on a cell autonomous signal derived from the X:A ratio. The differential regulation of the otu and ovo genes provides a mechanism for the female germline to incorporate both somatic and cell-autonomous inputs required for oogenesis.
Zygotic ovo activity is not essential for pole cell viability or proliferation during stages of embryogenesis. Pupal gonads fail to produce egg chambers indicating that the agametic adult phenotype is caused by a block in oogenesis before cyst formation, rather than the degeneration of existing egg chambers. ovo function is not essential for germline viability before pupariation.
Alternative splicing generates two types of transcripts from the ovo gene.
An insertion of a transgene containing the ovoD1 mutation onto an autosome can confer a dominant female sterile phenotype.
Phenotypic analysis of mutations suggests that ovo encodes a function necessary for normal development of the oocyte.
ovo appears to be involved in germ line sex determination and is linked in some manner to sex determination in the soma.
Molecular analysis of ovo revertants from a cross with the y v f mal strain demonstrate they have acquired either a gypsy or copia insertion at cytological location 4E.
Homozygous females and females of the genotype Df(1)HC244, SxlM1/ovo are sterile with ovaries devoid of germ cells: ovo must act downstream of Sxl or in a different pathway.
ovo is required for early female germ line maintenance but is not required for male germ line stability.
ovo mutants display short denticles that are reduced in number and an absence of dorsal hairs.
The expression of genes controlling neurogenesis is dependent on the previous activity of the genes controlling the development of the embryonic dorsal-ventral pattern.
All ovo alleles fully penetrant for female sterility; no male function for ovo+ known. Lack of zygotic activity results in complete absence of germ-line cells in adult female; reduction in numbers of germ cells first evident during early gastrulation. Homozygotes for weaker alleles produce germ cells, but oogenesis defective; egg chambers may degenerate prior to vitellogenesis or proceed through oogenesis and be oviposited, depending on allele; laid eggs are permeable to neutral red and never develop. Heterozygotes for two of the dominant alleles phenotypically similar to homozygotes for weak recessive alleles. Ovarian tumors formed in females carrying ovoD3 in heterozygous combination with the hypomorphic alleles, e.g., ovoD1rv20, or with snf. The ovoD2 mutation is partially suppressed by many Sxl alleles. ovoD1/+ females produce no eggs; extensively utilized in the selection of ovo+ germ-line clones. svb alleles are homozygous lethal. Many fewer denticles than wild type; remaining denticles small and with characteristic morphology. Denticles arranged in belts in the abdominal segments; absent from thoracic segments. Cell autonomous in mosaics; useful in studying embryonic mosaics.
Source for merge of: ovo CG15467
Annotations CG6824 and CG15467 merged as CG6824 (which corresponds to ovo) in release 3 of the genome annotation.
Recessive alleles, mostly recovered as revertants of dominant alleles, usually but not always, simultaneously mutant lzl; The lzl eye phenotype is cold-sensitive and semidominant. Most revertants are amorphic in that, when tested in heterozygous combination with ovoD1rv22 or ovoD1rv23, they have atrophic ovaries, with no egg chambers observable.
Source for identity of: ovo CG6824
