草鱼α-淀粉酶基因组织表达特征和早期发育的表达谱  

Expression analysis of α-amylase gene in various tissues and early development of Ctenopharyngodon idellus

作　　者：唐小红[1,2] 樊佳佳[1] 白俊杰[1,2] 

机构地区：[1]中国水产科学研究院珠江水产研究所,农业部热带亚热带水产资源利用与养殖重点实验室,广东广州510380 [2]上海海洋大学水产与生命学院,上海201306

出　　处：《海洋渔业》2015年第1期31-37,共7页Marine Fisheries

基　　金：国家科技支撑计划"草鱼新品种选育"(2012BAD26B02);国家高技术研究发展计划"草鱼重要经济性状相关基因的克隆及功能验证"(2011AA100403);现代农业产业技术体系建设专项资金"华南地区草鱼选育及分子辅助育种"(CARS-46-03);广东省战略性新兴产业核心技术攻关计划(2012A020800001)

摘　　要：为获知α-淀粉酶(α-amylase,AMY)在鱼体内的组织分布以及在鱼类早期发育过程中的特征,从消化酶的角度阐明鱼类对糖的利用机理,实验在获得草鱼(Ctenopharyngodon idellus)α-淀粉酶基因编码区序列的基础上,应用实时定量PCR(real-time PCR)检测了草鱼α-淀粉酶基因在不同组织和早期发育不同时期的相对表达量。序列分析结果显示:草鱼的α-淀粉酶的ORF框长1 539 bp,编码512个氨基酸,氨基酸同源性比对发现草鱼α-淀粉酶与其它物种的同源性很高,且在关键活性位点处均保守,其中与斑马鱼(Danio rerio)α-淀粉酶氨基酸的同源性最高,为92%,与人的同源性最低,为72%。对血液、心脏、肝胰脏、肾、肌肉、脑、前肠、中肠、后肠9个组织定量分析结果显示:草鱼α-淀粉酶基因在肝胰脏中的表达量最高,在前肠、中肠和后肠能检测到明显的表达,在心脏和肾脏仅能检测到微弱的表达。早期发育定量分析结果显示:从未受精卵到神经胚都没有检测到α-淀粉酶基因的表达,从器官形成期开始检测到微弱的表达,一直到出膜后48 h表达都很微弱,出膜72 h之后表达量升高较明显。对组织分布和早期发育的定量研究结果分析表明:肝胰脏并不是草鱼生成α-淀粉酶的唯一场所,在肠道中也有α-淀粉酶的合成;从出膜72 h仔鱼开口摄食之后,α-淀粉酶基因表达量增加得较明显,推测摄食能够促进α-淀粉酶基因的表达。To obtain the expression features of α-amylase （ct-AMY） gene in tissues and early development, and to illuminate the carbohydrate utilization of fish from digestive enzymes, we made relative quantitative studies on mRNA expression of α-amylase gene in different tissues and different developmental stages of grass carp （Ctenopharyngodon idellus ）by real time PCR based on the completed encoded sequences. As the sequence analysis showed： the a-amylase gene ORF was 1 539 bp in length and encoded 512 amino acids, and the amino acids sequence homology between grass carp AMY and other species was very high. The grass carp AMY showed the highest homology, 92% , with the α-amylase of zebrafish（Danio rerio） , and had the lowest homology, 72%, with human beings. Relative quantitative expression of α-AMY mRNA in blood, heart, hepatopancrea, kidney, muscle, brain, foregut, midgut and hindgut tissues showed ： the α-amylase gene expressed most in hepatopancrea, and was distinct in foregut, midgut and hindgut , and low in heart and kidney. And the analysis of relative quantitative expression of grass carp in early development showed： no α- AMY mRNA can be tested from unfertilized eggs to neurula , and the α-AMY began to express from organogenesis, but the expression was very low till 48 h after hatching. After 72 h after hatching, the expression of α-AMY increased obviously. Analyzing the tissue distribution and the expression pattern in early development, we could find out that hepatopancrea was not the only organ of grass carp to generate α- amylase, and there were also α-amylase synthesis in the gut. α-AMY increased obviously in 72 hours after hatching when the larvae began to feed. It was speculated that feeding can promote the expression of α- amylase.

关 键 词：Α-淀粉酶 草鱼 组织表达 早期发育 

分 类 号：Q954[生物学—动物学]