Pf-Dmrt4,a potential factor in sexual development in the pearl oyster Pinctada fucata

摘要

The mechanisms of sex determination and sex differentiation in the pearl oyster Pi:nctadafucata are currently poorly understood.We therefore investigated the roles of orthologs of the D:mrt gene family,key players in male gonad differentiation in mammals,in P.fucata sex differentiation and sexual development.Pf-Dmrt4 exhibits features typical of the Dmrt family,and displays significant homologies to the DMRT4 cluster.Pf-Dmrt4 mRNA expression in the gonads during a gametogenic cycle,measured by quantitative polymerase chain reaction,was maximal in mature individuals.Pf-Dmrt4 expression,demonstrated by in situ hybridization,was localized in the spermatozoa,spermatids,oocytes and vitellogenic oocytes.Knockdown of Pf-Dmrt4 with double-stranded RNA resulted in decreased mRNA expression levels.And Pf-Dmrt4-dsRNA-injected groups showed spawning-stage male gonads,with ruptured follicles and released spermatozoa.Our results enhance the understanding of sex determination and differentiation in P.fucata and suggest that Pf-Dmrt4 could be involved in male gonadal development,and maintenance of male gonadal function.