title: Sohlh2 affects differentiation of KIT positive oocytes and spermatogonia.
abstract: The differentiation programs of spermatogenesis and oogenesis are largely independent. In the early stages, however, the mechanisms partly overlap. Here we demonstrated that a germ-cell-specific basic helix-loop-helix (bHLH) transcription factor gene, Sohlh2, is required for early spermatogenesis and oogenesis. SOHLH2 was expressed in mouse spermatogonia from the undifferentiated stage through differentiation and in primordial-to-primary oocytes. Sohlh2-null mice, produced by gene targeting, showed both male and female sterility, owing to the disrupted differentiation of mature (KIT(+)) spermatogonia and oocytes. The Sohlh2-null mice also showed the downregulation of genes involved in spermatogenesis and oogenesis, including the Sohlh1 gene, which is essential for these processes. Furthermore, we showed that SOHLH2 and SOHLH1 could form heterodimers. These observations suggested that SOHLH2 might coordinate with SOHLH1 to control spermatogonial and oocyte genes, including Sohlh1, to promote the differentiation of KIT(+) germ cells in vivo. This study lays the foundation for further dissection of the bHLH network that regulates early spermatogenesis and oogenesis.
authors.affiliation: Division of Stem Cell Regulation Research (G6), Osaka University Graduate School of Medicine, Suita, Osaka 565-0871, Japan.
authors.forename: Shuichi
authors.initials: S
authors.lastname: Toyoda
authors.forename: Tatsushi
authors.initials: T
authors.lastname: Miyazaki
authors.forename: Satsuki
authors.initials: S
authors.lastname: Miyazaki
authors.forename: Takuji
authors.initials: T
authors.lastname: Yoshimura
authors.forename: Mayu
authors.initials: M
authors.lastname: Yamamoto
authors.forename: Fumi
authors.initials: F
authors.lastname: Tashiro
authors.forename: Eiji
authors.initials: E
authors.lastname: Yamato
authors.forename: Jun-ichi
authors.initials: J
authors.lastname: Miyazaki
mesh_terms: D000818:Animals; D051792:Basic Helix-Loop-Helix Proteins / Q000172:deficiency / Q000235:genetics / Q000378:metabolism*; D015153:Blotting, Western; D002454:Cell Differentiation; D002460:Cell Line; D005260:Female; D005455:Fluorescent Antibody Technique; D018507:Gene Expression Regulation, Developmental; D006801:Humans; D008297:Male; D051379:Mice; D009865:Oocytes / Q000166:cytology* / Q000378:metabolism*; D009866:Oogenesis / Q000235:genetics; D011485:Protein Binding; D019009:Proto-Oncogene Proteins c-kit / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013091:Spermatogenesis / Q000235:genetics; D013093:Spermatogonia / Q000166:cytology* / Q000378:metabolism*; D013737:Testis / Q000166:cytology / Q000378:metabolism
chemical_list: D051792:Basic Helix-Loop-Helix Proteins; D019009:Proto-Oncogene Proteins c-kit; C511466:Sohlh1 protein, mouse; C515516:Sohlh2 protein, mouse