title: Mutation of Gonadal soma-derived factor induces medaka XY gonads to undergo ovarian development.
abstract: Gonochoristic species have a bipotential gonad that develops into a testis or an ovary. In species whose sex is determined by a genetic factor, the expression of a sex-determining gene is the first cue that directs the development of a bipotential gonad. Subsequent expression of downstream genes induces the gonad to develop into a testis or an ovary. The TGF-ß family member Gonadal soma-derived factor (Gsdf) is thought to be an important gene for gonadal development in teleost fish, and it is expressed at higher levels in the testis than in the ovary from early to mature stages. However, there is little functional information about the gene. In this study, we targeted the Gsdf coding region in the medaka fish Oryzias latipes using transcription activator-like effector nucleases (TALENs) and studied the phenotypes of the Gsdf mutant medaka. Although normal and heterozygous XY gonads developed into a testis, all XY gonads with a homozygous mutation in Gsdf developed into an ovary at early developmental stages. However, two-thirds of Gsdf mutant XY gonads developed into testes in the adult stages. These results demonstrate that although a gonad can develop into a complete testis in the absence of Gsdf, Gsdf function is critical for directing the bipotential gonad at early developmental stages. Therefore, Gsdf is an endogenous inducer of testicular development similar to a master sex-determining gene.
authors.affiliation: United Graduate School of Agricultural Science, Tokyo University of Agriculture and Technology, Tokyo 183-8509, Japan; Center for Bioscience Research and Education, Utsunomiya University, Tochigi 321-8505, Japan.
authors.forename: Takuto
authors.initials: T
authors.lastname: Imai
authors.affiliation: Center for Bioscience Research and Education, Utsunomiya University, Tochigi 321-8505, Japan.
authors.forename: Kentaro
authors.initials: K
authors.lastname: Saino
authors.affiliation: United Graduate School of Agricultural Science, Tokyo University of Agriculture and Technology, Tokyo 183-8509, Japan; Center for Bioscience Research and Education, Utsunomiya University, Tochigi 321-8505, Japan. Electronic address: matsuda@cc.utsunomiya-u.ac.jp.
authors.forename: Masaru
authors.initials: M
authors.lastname: Matsuda
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D030801:Animals, Genetically Modified; D001483:Base Sequence; D004247:DNA / Q000235:genetics; D005260:Female; D029941:Fish Proteins / Q000235:genetics; D018507:Gene Expression Regulation, Developmental; D055786:Gene Knockout Techniques; D006066:Gonads / Q000254:growth & development*; D008297:Male; D008969:Molecular Sequence Data; D009154:Mutation; D009990:Oryzias / Q000235:genetics* / Q000254:growth & development*; D010053:Ovary / Q000254:growth & development; D010641:Phenotype; D019849:Sex Determination Processes / Q000235:genetics*; D013737:Testis / Q000254:growth & development; D016212:Transforming Growth Factor beta / Q000235:genetics; D014960:X Chromosome / Q000235:genetics; D014998:Y Chromosome / Q000235:genetics
chemical_list: D029941:Fish Proteins; D016212:Transforming Growth Factor beta; D004247:DNA
keywords: Gonadal development; Gsdf; Medaka; Oryzias latipes; Sex reverse; Sexual development