The sex-determining genes are found to be variable among different fish species. Yellow catfish(Pelteobagrus fulvidraco) is an important aquaculture fish species in China with XX/XY sex-determining type. Recently, YY super-male yellow catfish has been successfully produced by combining hormonalinduced sex reversal method with sex chromosome-linked markers. Here, we identified a novel PDZ domain-containing gene in yellow catfish designated as pfpdz1, in whose intron the sex-linked marker was located. The coding sequence of pfpdz1 in Y chromosome was identical to that in X chromosome except a missense SNP(A/T) that changes an amino acid(E8V) in the N-terminal region. Pfpdz1 displayed male-specific expression during sex differentiation. Overexpression of pfpdz1 using additive transgenesis induces XX ovary to differentiate into testis-like tissue, while the targeted inactivation of pfpdz1 in Y chromosome using CRISPR/Cas9-mediated mutagenesis triggers ovarian differentiation. Furthermore,we demonstrated that pfpdz1 initiates testicular differentiation through upregulating expression of amh, dmrt1 and sox9a1, as well as downregulating expression of cyp19a1, foxl2 and wnt4. Our data provide functional evidence that pfpdz1 is significant for male differentiation and maintenance in yellow catfish.
the National Natural Science Foundation of China(31672635)
China Agricultural Research System(CARS-46).
Cheng Dan is a post-doctoral researcher in College of Fisheries,Huazhong Agriculture University.He received his B.S.in Biotechnology from South-Central University of Nationalities and his Ph.D.degree from Institute of Hydrobiology,Chinese Academy of Sciecnes.His major research area concentrates on the genetics basis of sex determination and sexual differentiation in yellow catfish and sex-control application in fish breeding;Corresponding authors:Jian-Fang Gui is a Professor in Institute of Hydrobiology, Chinese Academy of Sciences.His research focuses on basic biology and biotechnologies with particular emphasis on fish genetics and breeding.Dr.Gui and his colleagues performed extensive studies on reproduction and development mechanisms of gibel carp (Carassius auratus gibelio).They have exploited new directions of molecular regulation networks that are related to economically important traits and molecular breeding, isolated Y chromosome-specific and X chromosomespecific markers,and thereby created the markerassisted sex control breeding biotechnology.Dr.Gui is an Academician of the Chinese Academy of Sciences and a member of the Third World Academy of Sciences. E-mail addresses:email@example.com;Corresponding authors:Jie Mei received his B.S.degree in Biotechnology from Wuhan University and earned his Ph.D.degree from Institute of Hydmbiology,Chinese Academy of Sciecnes. Dr.Mei completed his postdoctoral training at the UT Southwestern Medical Center.In 2012,he joined the faculty of Huazhong Agricultural University as a professor in the College of Fisheries.The major goal of his group is to reveal the genetics basis of sex determination and sexual dimorphism in fish species and use sexcontrol technology in fish breeding.E-mail addresses:firstname.lastname@example.org