鲤性腺GnRH-GtH旁分泌系统的发现及其在生长/生殖调控中的作用  

The Discovery of GnRH-GtH Paracrine System in Common Carp (Cyprinus carpio) Gonad and Its Roles in Growth and Reproduction Regulation

作　　者：俞薇[1,2] 曹梦西[1,3] 陈戟[1] 贾少婷[1,2] 李勇明[1] 朱作言[1] 胡炜[1] 

机构地区：[1]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 [2]中国科学院大学,北京100049 [3]江汉大学环境与健康研究院,武汉430056

出　　处：《农业生物技术学报》2017年第9期1516-1525,共10页Journal of Agricultural Biotechnology

基　　金：国家自然科学基金(No.31325026和No.31672661)

摘　　要：鱼类生长与生殖间存在复杂的网络调控关系,本研究以黄河鲤(Cyprinus carpio)和转草鱼(Ctenopharyngodon idellus)生长激素基因(growth hormone,gh)鲤为研究对象,采用荧光定量PCR、免疫荧光、原位杂交及体外孵育实验等方法,探索了鲤性腺水平的生殖调控及其与生长的关系。发现鲤精巢和卵巢中存在促性腺激素α亚基(gonadotropin subunit alpha,gthα)、促卵泡激素β亚基(follicle stimulating hormone subunit beta,fshβ)、促黄体生成激素β亚基(luteinizing hormone subunit beta,lhβ)、促性腺激素释放激素3(gonadotropin-releasing hormone 3,gnrh3)、生长激素受体(growth hormone receptor,ghr)和4种GnRH受体m RNA。免疫荧光检测发现GTHα和LHβ主要定位在生殖细胞周围的体细胞和初级精母细胞中。进一步通过卵巢碎片体外GnRH孵育实验证实鲤性腺中存在独立于下丘脑-垂体-性腺轴的GnRH-GtH旁分泌系统。本研究还发现转gh鲤与对照鲤性腺中gnrh3及gthα、fshβ和lhβ的表达量存在显著差异,高浓度的GH促进处于初级生长期卵巢GnRH-GtH系统中gnrh3、gthα、fshβ和lhβ的转录,但抑制次级生长阶段卵巢中相应基因的转录。结果表明,鲤性腺中不仅存在GnRH-GtH旁分泌系统,并且在鲤的生长与生殖调控间扮演了重要角色,本研究为揭示鱼类生长与生殖间的调控机制积累了科学资料。Growth and reproduction are closely related in fish. Herely, the hormone cross-talk between the two systems in the gonad has been analyzed with Common carp （Cyprinus carpio） and growth hormone （gh） transgenic common carp by using real qRT-PCR, immunofluorescence, in situ hybridization, and in vitro incubation. The expression of gonadotropin hormone alpha （gthα）, follicle-stimulating hormone beta （fshβ）, luteinizing-stimulating hormone beta （lhβ）, gonadotropin-releasing hormone 3 （gnrh3）, growth hormone receptor （ghr） and 4 GnRH receptor mRNA were detected in testis and ovary of common carp.Immunofluorescence showed that GTHa and LHβ were localized mainly in the somatic cells and primary sperm cells of the gonads. In vitro incubation of ovary fractions with GnRH confirmed the existence of gonadal GnRH-GtH paracrine system, which was independent of the hypothalamus-pituitary-gonad axis. The expression levels of gnrh3, gthot, fshβ and lhβ mRNA were significantly different in the gonad of GH- transgenic carp when compared with non-transgenic carp. Further analysis in vitro showed that GH up- regulated the expression of gnrh3, gthα, fshβ and lhβ in the ovarian GnRH-GtH system at primary growth stages. But the signals were inhibited in the ovarian at the secondary growth stages. Our results confirmed the GnRH-GtH paracrine system in gonad and uncovered its important role in the interaction between growth and reproduction in common carp, which provides scientific data to reveal the regulation mechanism between growth and reproduction in fish.

关 键 词：鲤 性腺 生长 生殖 GnRH—GtH旁分泌系统 

分 类 号：S917.4[农业科学—水产科学]