Molecular cloning and mRNA expression pattern of Sox10 in Paramisgurnus dabryanus.

A number of genetic studies have established that Sox10 involved in a wide range of developmental processes including sex differentiation and neurogenesis in vertebrates. A Sox10 homologue was cloned from brain of Paramisgurnus dabryanus by using homologous cloning and RACE method, designated as PdSox10. The full-length cDNA of PdSox10 contains a 312 bp 5' UTR, a 1,476 bp open reading frame (ORF) encoding 492 amino acids and a 262 bp 3' UTR (Accession no.: JQ217143). The overall topology of the phylogenetic tree shows that the PdSox10 fits within the Sox10 clade. During embryogenesis, PdSox10 gene seemed to be de novo synthesized in the embryos from gastrulae stage. From the somitogenesis stage and thereafter, distinct expression of PdSox10 was observed in the medial neural tube, extending from the hindbrain through the posterior trunk. In adult, PdSox10 mRNA was detected primarily in the gonads, as well as in brain and heart by RT-PCR. In situ hybridization on gonadal sections further demonstrated that PdSox10 is expressed especially in premature germ cells, in early perinucleolus stage oocytes and cortical-alveolar stage oocytes in ovaries and in spermatogonia and spermatocytes in testes. These preliminary findings suggested that PdSox10 is highly conserved during vertebrate evolution and involved in a wide range of developmental processes including neurogenesis and sex differentiation in vertebrates.