【作者】 曹继增； 周同； 陈国彬； 邹桂伟； 梁宏伟；

【Author】 CAO Ji-Zeng;ZHOU Tong;CHEN Guo-Bin;ZOU Gui-Wei;LIANG Hong-Wei;College of Fisheries and Life Science,Shanghai Ocean University;Yangtze River Fisheries Research Institute,Chinese Academy of Fisheries Science;

【机构】 上海海洋大学水产与生命科学学院； 中国水产科学研究院长江水产研究所；

【摘要】 中华鳖(Pelodiscus sinensis)是中国重要的水产养殖品种,具有显著的性别二态性,雄性个体比雌性个体具有更高的经济价值。在脊椎动物中,已有多个R-Spondin家族蛋白与性别分化机制密切相关;然而,它们在中华鳖性别分化过程中的作用尚不清楚。外源激素如雌二醇(E2)也会影响中华鳖的性别分化并诱导其性逆转。本研究探讨了E2对中华鳖胚胎发育及R-Spondin 2(Rspo2)和R-Spondin 3(Rspo3)基因表达的影响。我们克隆了中华鳖Rspo2、Rspo3基因,并分析了它们在不同组织中的表达模式。与其他物种的蛋白序列比对分析表明,中华鳖RSPO2和RSPO3序列保守。此外,系统发育分析表明,中华鳖RSPO2、RSPO3与其他龟类的这两个蛋白亲缘关系较近。此外,Rspo2、Rspo3在成鳖脑和性腺中高表达,在卵巢中的表达量显著高于精巢(P<0.05)。我们还评估了3个浓度的E2(1.0,5.0和10.0mg/mL)在胚胎发育阶段注射到鳖蛋中Rspo2和Rspo3的表达情况。结果表明,E2上调Rspo2和Rspo3的表达,且在不同胚胎发育阶段(13～20期)的表达趋势不同。这些发现为今后研究中华鳖性别分化的分子机制奠定了基础。更多还原

【Abstract】 The Chinese soft-shelled turtle,Pelodiscus sinensis,is an important aquaculture species in China that exhibits distinct sexual dimorphism;male individuals are economically more valuable than females.In vertebrates,several R-spondin family proteins have been associated with sex differentiation mechanisms;however,their involvement in P.sinensis sex differentiation is unclear.Exogenous hormones such as estradiol(E2) also influence the sex differentiation of P.sinensis and induce sexual reversal.In the present study,we investigated the effects of E2 on the embryonic development of P.sinensis and the expression of R-spondin 2(Rspo2) and R-spondin 3(Rspo3).We amplified P.sinensis Rspo2 and Rspo3 and analyzed their expression patterns in different tissues.Comparative analyses with protein sequences from other species elucidated that P.sinensis RSPO2 and RSPO3 sequences were conserved.Moreover,phylogenetic analysis revealed that P.sinensis RSPO2 and RSPO3 were closely related to these two proteins from other turtle species.Furthermore,Rspo2 and Rspo3 were highly expressed in the brain and gonads of adult turtles,with significantly higher expression in the ovaries than in the testes(p < 0.05).We also evaluated the expression of Rspo2 and Rspo3 after the administration of three concentrations of E2(1.0,5.0,and 10.0 mg/mL) to turtle eggs during embryonic development.The results revealed that E2 upregulated Rspo2 and Rspo3,and the expression trends varied during different embryonic developmental stages(stages 13–20).These findings lay the groundwork for future investigations into the molecular mechanisms involved in the sex differentiation of Chinese soft-shelled turtles.更多还原