摘要: |
胰岛素(Insulin,Ins)作为动物体内最保守的小分子蛋白,是调控血糖、脂肪和蛋白质代谢的重要激素,同时也对卵生动物的卵黄合成发挥着重要作用,但在鱼类中研究相对较少。为探讨银鲳胰岛素对卵黄合成的影响,从转录组数据中获得了银鲳3个胰岛素insulin (ins)、insulin-like (ins-like)和insulin-2 (ins-2)基因全长cDNA序列。序列分析表明,银鲳3个胰岛素基因的氨基酸序列具有胰岛素基因的典型特征,包含NH-2端分泌的信号肽和由B链、C链和A链组成的IIGF。系统进化树分析表明,哺乳类ins单独为一簇,鱼类ins和ins-2成一簇及鱼类ins-like单独成一簇。组织表达特征分析表明,银鲳胰岛素家族3个基因ins、ins-2和ins-like在各个组织中广泛表达,但是不同组织的3个基因表达水平不相同。对不同发育阶段的银鲳肝脏和卵巢组织中3个胰岛素基因和3个卵黄蛋白原(vitellogenin,vtg)基因的表达量进行了分析,结果显示,所有银鲳ins和vtg基因在肝脏和卵巢中的表达趋势一致,从Ⅱ期至Ⅳ期肝脏和卵巢中逐渐升高,并在Ⅳ期达到最高值,从Ⅳ期至Ⅵ期表达量显著下降。研究结果表明,鱼类胰岛素与卵黄原蛋白在肝脏和卵巢表达具有相同趋势,这是首次在鱼类中研究胰岛素基因与性腺发育相关性的研究。而根据昆虫中已报道胰岛素直接调控卵黄原蛋白的合成,我们推测鱼类中胰岛素可能也参与调控卵黄蛋白的合成,两者密切相关,可为深入探究鱼类胰岛素基因的功能和机制提供新思路。 |
关键词: 胰岛素 卵黄蛋白原 卵巢 肝脏 银鲳 |
DOI:10.11693/hyhz20220500117 |
分类号: |
基金项目:浙江省海水增养殖重点实验室开放课题项目,2021KF004号;宁波市公益类科技计划项目,2020N3035号。 |
附件 |
|
MOLECULAR IDENTIFICATION OF INSULIN GENE AND ITS ASSOCIATIVE EXPRESSION WITH VITGELLOGENIN GENE IN PAMPUS ARGENTEUS |
YANG Yang1,2, NING Chao3, WANG Ya-Jun3
|
1.Marine Fishery Institute of Zhejiang Province, Zhoushan 316021, China;2.Key Laboratory of Mariculture and Enhancement of Zhejiang Province, Zhoushan 316021, China;3.School of Marine Science, Ningbo University, Ningbo 315832, China
|
Abstract: |
The insulin (Ins), an evolutionarily conserved molecule among animals, is an important hormone regulating carbohydrate, fat, and protein metabolism, and also plays an important role in vitellogenesis in oviparous animals. However, there are a relatively few studies in fish. To explore the effects of silver pomfret (Pampus argenteus) on vitellogenesis, the full-length cDNA sequences of insulin (ins), insulin-2 (ins-2), and insulin-like (ins-like) genes were obtained from liver transcriptome sequencing data of silver pomfret. Sequence analysis showed that the amino acid sequences of the three insulin genes of silver pomfret had typical characteristics of insulin gene, including signal peptide secreted from NH-2 terminal, and IIGF composed of A-, C-and B-chain. Phylogenetic tree analysis showed that mammals Ins clustered, fish Ins and Ins-2 clustered, and fish Ins-like clustered, separately from each other. Real-time quantitative PCR (qRT-PCR) analysis showed that the three insulin genes were widely expressed in various tissues of healthy pomfret, but their expression levels were different in different tissues. The qRT-PCR analysis of three insulin and three vitellogenin(vtg) genes in ovary and liver at different developmental stages were analyzed. This study firstly showed that all of the insulin and vtggenes were expressed in liver and ovary in fish. And the expression trend is consistent, gradually increased from stages Ⅱ to Ⅳ in liver and ovary, and reached the highest value in stage Ⅳ, then the expression levels decreased significantly from stages Ⅳ to Ⅵ. Therefore, based on the finding in insect, we inferred that there is a close relationship between fish insulin and vtg, and insulin might participate in regulating vtg synthesis. This study provided a new thought for in-depth exploration of the function and mechanism of fish insulin. |
Key words: insulin vitellogenin ovary liver Pampus argenteus |