analysis of medaka sox9 orthologue reveals a conserved role in germ cell maintenance分析青鳉sox9 orthologue揭示了一个守恒在生殖细胞的维护作用.pdfVIP

Analysis of Medaka sox9 Orthologue Reveals a Conserved Role in Germ Cell Maintenance 1 1 1,2 3 4 Shuhei Nakamura , Ikuko Watakabe , Toshiya Nishimura , Atsushi Toyoda , Yoshihito Taniguchi , Minoru Tanaka1,2* 1 Laboratory of Molecular Genetics for Reproduction, National Institute for Basic Biology, Okazaki, Japan, 2 Department of Basic Biology, The Graduate University for Advanced Studies (SOKENDAI), Okazaki, Japan, 3 Comparative Genomics Laboratory, National Institute of Genetics, Mishima, Japan, 4 Department of Preventive Medicine and Public Health, School of Medicine, Keio University Shinanomachi 35, Tokyo, Japan Abstract The sex determining gene is divergent among different animal species. However, sox9 is up-regulated in the male gonads in a number of species in which it is the essential regulator of testis determination. It is therefore often discussed that the sex determining gene-sox9 axis functions in several vertebrates. In our current study, we show that sox9b in the medaka (Oryzias latipes) is one of the orthologues of mammalian Sox9 at syntenic and expression levels. Medaka sox9b affects the organization of extracellular matrices, which represents a conserved role of sox9, but does not directly regulate testis determination. We made this determination via gene expression and phenotype analyses of medaka with different copy numbers of sox9b. Sox9b is involved in promoting cellular associations and is indispensible for the proper proliferation and survival of germ cells in both female and male medaka gonads. Medaka mutants that lack sox9b function exhibit a seemingly paradoxical phenotype of sex reversa