黄鳝性腺自然逆转过程中vasa基因的表达分析  

Expression of gene vasa during gonadal natural sex reversal of ricefield eel Monopterus albus

作　　者：吕道远[1] 宋平[1] 陈云贵[1] 彭茂宇[1] 桂建芳[2] 

机构地区：[1]武汉大学生命科学院发育生物学教育部重点实验室,武汉430072 [2]中国科学院水生生物研究所淡水生态与生物技术国家重点实验室,武汉430072

出　　处：《动物学报》2005年第3期469-475,共7页ACTA ZOOLOGICA SINICA

基　　金：国家"863"项目(2001AA222071);国家自然科学基金项目(30270675)资助~~

摘　　要：本研究采用RNA反义探针原位杂交技术,对vasa基因在黄鳝(Monopterusalbus)性腺发育过程中的表达情况进行了分析。结果表明:vasamRNA在Ⅰ、Ⅱ、Ⅲ期卵母细胞的胞质中均匀分布,在Ⅳ、Ⅴ期卵母细胞中vasamRNA有向胞质外周皮层迁移集中的趋势,但不明显;退化的卵粒也呈现vasamRNA阳性反应;在Ⅲ、Ⅳ期卵巢的被膜中检测到带有vasa阳性信号的细胞,这些细胞可能是待向精原细胞分化、迁移到卵巢被膜上的原始生殖细胞(Primordialgermcell,PGC),在性逆转过程中这些PGC可能由卵巢被膜迁移到精小叶中并发育成精子;在成熟精巢中,vasa在精原细胞和初级精母细胞中表达。进一步采用碱性磷酸酶染色法分析黄鳝卵巢及精巢后发现:在卵巢中,除了卵母细胞外,卵巢被膜中也检测到了带有碱性磷酸酶阳性信号的细胞;在成熟精巢中,只在生殖腺囊内的雄性生殖细胞中检测到碱性磷酸酶,而精巢被膜中没有检测到带有碱性磷酸酶阳性信号的细胞。本研究结果初步表明:黄鳝的雄性生殖细胞可能起源于雌性阶段卵巢被膜中的原始生殖细胞[动物学报51(3):469-475,2005]。Using in situ hybridization with DIG antisense RNA probe, we detected the expression of gene vasa during gonadal development of Monopterus albus. During oogenesis, the expression of vasa mRNA can be detected in the cytoplasm of Ⅰ,Ⅱ, Ⅲ stage oocytes. The vasa mRNA concentration was not obvious in the cortical region of stage Ⅳ,Ⅴ oocytes. The signals of vasa mRNA can also be observed in degenerated oocytes. We detected some vasa mRNA positive cells in the membrane of Ⅲ,Ⅳ stage ovary, and these may be the primordial germ cells (PGC) which migrate to the membrane of the ovary and will differentiate to spermatogenia. These PGCs will migrate to the seminiferous tubule and develop into spermatids during sexual reversal. The expression of vasa mRNA in the mature testis is restricted to the spermatogenia and spermatocytes. We examined the Monopterus albus ovary and testis by alkaline phosphatase staining and found that there are alkaline phosphatase positive cells in the membrane of the ovary. In mature testis, the male germ cells in the gonadal sac are alkaline phosphatase positive while no alkaline phosphatase positive cells are found in the testis membrane. The results suggest that the male germ cells of Monopterus albus may derive from the PGCs in the membrane of ovary.

关 键 词：黄鳝 性逆转 VASA基因 基因表达 原位杂交 性腺发育 原始生殖细胞 碱性磷酸酶 

分 类 号：Q786[生物学—分子生物学]