Zhang Rui, Zhang Shengzhou, Zhu Xue, Zhou Yongkang, Wu Xiaobing
Key Laboratory for Conservation and Use of Important Biological Resources of Anhui Province, College of Life Sciences, Anhui Normal University, Wuhu, Anhui 241000, China.
Key Laboratory for Conservation and Use of Important Biological Resources of Anhui Province, College of Life Sciences, Anhui Normal University, Wuhu, Anhui 241000, China.
Anim Reprod Sci. 2015 May;156:40-50. doi: 10.1016/j.anireprosci.2015.02.008. Epub 2015 Feb 28.
The follicle-stimulating hormone (FSH) plays a central role in vertebrate reproduction, with the actions of FSH mediated by FSH receptors (FSHRs) on the granulosa cells of the ovary. The present study reports the cloning and characterization of FSHR in Chinese alligator, Alligator sinensis (caFSHR), and its tissue distribution and mRNA expression changes during the reproductive cycle. The mature protein of caFSHR displays typical features of the glycoprotein hormone receptor family, but also contains some remarkable differences when compared with other vertebrate FSHRs. The deduced amino acid sequence of the caFSHR shares identity of 85% with Chinese softshell turtle, 84-87% with birds, 77-78% with mammals, 67-73% with amphibians and 51-58% with fishes. Phylogenetic tree analysis of the FSHR amino acid sequence indicated that alligators cluster into the bird branch. Tissue expression analysis showed that caFSHR was not only expressed in the ovary, but also in the stomach, intestine, pancreas liver and oviduct at similar levels, while it was not detectable in heart, thymus or thyroid. Expression of caFSHR in the ovary is high in May (breeding prophase) and peaks in July during the breeding period, where it is maintained at high levels through September (breeding anaphase). Expression decreases significantly in November (hibernating period) and then remains relatively low from January to March (hibernating period). These temporal changes in FSHR expression suggest that it plays an important role in promoting ovarian development during the female reproductive cycle of Chinese alligator.
促卵泡激素（FSH）在脊椎动物繁殖中起核心作用，FSH的作用由卵巢颗粒细胞上的FSH受体（FSHR）介导。本研究报告了扬子鳄（Alligator sinensis）FSHR（caFSHR）的克隆与鉴定，以及其在生殖周期中的组织分布和mRNA表达变化。caFSHR的成熟蛋白具有糖蛋白激素受体家族的典型特征，但与其他脊椎动物的FSHR相比也存在一些显著差异。caFSHR推导的氨基酸序列与中华鳖的一致性为85%，与鸟类的一致性为84 - 87%，与哺乳动物的一致性为77 - 78%，与两栖动物的一致性为67 - 73%，与鱼类的一致性为51 - 58%。FSHR氨基酸序列的系统发育树分析表明，扬子鳄聚在鸟类分支中。组织表达分析显示，caFSHR不仅在卵巢中表达，在胃、肠、胰腺、肝脏和输卵管中也有相似水平的表达，而在心脏、胸腺或甲状腺中未检测到。caFSHR在卵巢中的表达在5月（繁殖前期）较高，在7月繁殖期达到峰值，并在9月（繁殖后期）维持在高水平。11月（冬眠期）表达显著下降，然后在1月至3月（冬眠期）保持相对较低水平。FSHR表达的这些时间变化表明，它在扬子鳄雌性生殖周期中促进卵巢发育方面发挥重要作用。
