日本沼虾Mnfoxl2基因在早期性别分化及雌雄生长差异中的作用

The oriental river prawn (Macrobrachium nipponense) shows significantly growth difference between male and female. The males grow faster and gain more weight at harvest time than females, thus the all male population breeding would be dramatically economic. The researches on sex-determination and sex-differentiation mechanisms would provide basic information for sex-control and all-population breeding. Recently studies showed that the sex-determination and sex growth difference of crustacean species was regulated by the gene expression on growth axis. Our previous studies confirmed that Forkhead box protein L2 (Mnfoxl2) was dramatically expressed in testes, suggesting that Mnfoxl2 is a new male development related genes in M. nipponense. Thus, in order to analysis of the relationship between Mnfoxl2 and M. nipponense growth, RNA interference (RNAi) is used to block the Mnfoxl2 expression in full sibs of M. nipponense larvae, further combined with the studies of male and female differentiation ratio, the volume of sex hormone and the regulatory relationship with the genes on growth axis and reproductive axis, analyzing the Mnfoxl2 function in sex-differentiation and sex growth difference. This project will carry out the function of Mnfoxl2 in sex-differentiation mechanism and the relationship with sex growth difference, providing basic information for sex-control and all-male breeding techniques.

同龄日本沼虾存在雌雄个体生长差异，雄虾生长速度及收获期规格显著高于雌虾，全雄虾养殖的经济效益显著。认识日本沼虾的性别决定和性别分化机制是其性别调控和全雄制种技术的基础。研究证实，虾类性别决定及其雌雄生长差异与其生长轴基因表达相关。本课题组前期研究获得日本沼虾雄性发育相关新基因--叉头框蛋白L2（Mnfoxl2），且发现该基因在精巢中高表达。在此基础上，本项申请拟以日本沼虾全同胞家系幼体为研究材料，利用RNA干扰（RNAi）技术，在日本沼虾性别分化早期，阻碍Mnfoxl2的表达，并结合雌雄分化比例、性激素分泌检测和与生长轴生殖轴基因调控分析，研究Mnfoxl2基因与日本沼虾生长的调控关系，分析该基因对幼龄日本沼虾性别分化以及雌雄生长差异的影响。通过该项研究，以期揭示Mnfoxl2基因在日本沼虾性别分化过程中作用及其与雌雄生长差异的关系，为建立日本沼虾性别控制技术和形成全雄虾制种技术奠定基础。