布氏鲳鲹GHRH基因克隆、组织和胚胎表达模式

促生长激素释放激素(growth hormone releasing hormone, GHRH)主要生物学功能是刺激垂体细胞分泌生长激素,已被证实是动物体生长轴的重要调控因子之一,布氏鲳鲹是一种生长快速的海洋鱼类,为了揭示其代谢旺盛的调节机制,本研究从GHRH入手,利用RACE技术和qPCR方法对布氏鲳鲹GHRH基因进行了克隆、组织和胚胎表达模式研究。实验结果显示,布氏鲳鲹GHRH基因cDNA序列全长1019bp,5’UTR、3’UTR长度分别为327 bp和164 bp,开放阅读框528 bp,共编码175个氨基酸;同源性分析结果表明,布氏鲳鲹GHRH基因与其它鲈形目鱼类的同源性在91%以上。布氏鲳鲹GHRH基因的表达区域大多都集中在中枢系统,其中下丘脑表达量最高;GHRH在受精卵期到后续发育过程中均检测到表达,其表达水平在仔鱼期达到最高。序列分析、组织及胚胎表达的结果表明,布氏鲳鲹GHRH的调节模式仍然可能通过下丘脑调节垂体释放GH,GHRH在个体发育的较早阶段即开始发挥作用。本研究掌握了布氏鲳鲹GHRH基因的基本规律,为进一步研究生长轴的调控提供了理论参考。

Cloning,Tissue and Embryo Expression Patterns of GHRH Gene in Trachinotus blochii

The main biological function of growth hormone releasing hormone(GHRH) is to stimulate pituitary cells to secrete growth hormone. It has been proved to be one of the important regulatory factors of animal growth axis. The Trachinotus blochii is a rapid growth of marine fish. In order to reveal the regulatory mechanism of its metabolism. This study starts with GHRH, we used rapid amplification of complementary DNA(cDNA) ends(RACE method) and PCR application to clone and expression analysis from Trachinotus blochii. The results showed that the full length of GHRH c DNA was 1 019 bp, including a 5’untranslated regions(UTR) of 327 bp and a 3’UTR of 164 bp. The open reading frame(ORF) was 528 bp, which encoded a putative protein of 175 amino acids. The results of homology analysis showed the homology between GHRH gene and other perciformes fish homology was more than 91%. The expression region of Trachinotus blochii GHRH gene were mostly in the central nervous system, in which the hypothalamus expression was the highest. The GHRH was detected during fertilization and subsequent development, and the expression level reached the highest in larval stage. The results of sequence analysis, tissue and embryo expression show that the Trachinotus blochii GHRH regulation mode can still release GH through the hypothalamic regulation of pituitary, and the GHRH has began to play a role in the early stage of ontogeny. In this study, we grasp the basic rules of Trachinotus blochii GHRH gene, and the regulation of growth axis for further research provides a theoretical reference.