马氏珠母贝TOR基因cDNA的克隆与组织表达分析

Cloning and Expression of TOR Gene from Pinctada martensii

TOR(target of rapamycin)是一类进化上非常保守的蛋白激酶,参与调节多种生化代谢,协调蛋白质的生物合成和降解。本研究采用c DNA末端快速扩增技术(RACE),克隆获得了马氏珠母贝TOR基因c DNA全长序列(pm-TOR);同时利用荧光定量技术检测了pm-TOR基因m RNA在马氏珠母贝各个组织中的表达含量。结果表明:pm-TOR基因c DNA序列全长9 220 bp,开放阅读框(ORF)长7 488 bp,编码2 495个氨基酸,5'非翻译区(5'UTR)长157 bp,3'UTR长1 575 bp。氨基酸序列同源比对分析显示pm-TOR氨基酸序列与其他物种具有较高的保守性,与牡蛎(Crassostrea gigas)的TOR的序列相似度为79%。荧光定量PCR数据分析显示,TOR基因的m RNA在马氏珠母贝血液、性腺、肝胰脏、外套膜、闭壳肌和鳃组织中均有表达,其中肝胰脏和性腺中表达量较高,血液中表达量较低。本研究为进一步阐述TOR在马氏珠母贝中生长和发育调控中的作用提供理论基础。

TOR(target of rapamycin) is an evolutionarily conserved protein that plays a crucial role in the biochemical metabolism and protein synthesis. In this study, using rapid amplification of c DNA ends technology(RACE), the full length of TOR gene was obtained from Pinctada martensii(pm-TOR); and Real-time PCR was used to detect the tissue-specific expression of TOR in Pinctada martensii. The results showed that the obtained full length of pm-TOR c DNA was 9 220 bp, containing an open reading frame(ORF) of 7 488 bp encoding 2 495 amino acid residues. The a 5' untranslated region(5' UTR) was 157 bp and the 3' UTR was 1 575 bp. Multiple sequence alignment indicated that TOR be highly conservative among species and TOR had 79% sequence identity with that from Crassostrea gigas. Quantitative real-time PCR analysis demonstrated that pm-TOR m RNA was constitutively expressed in hemocyte, gonad, hepatopancreas, mantle, adductor muscle and gill. The pm-TOR m RNA expression level was highly in hepatopancreas, gonad, lowly in hemocyte. These studies might provide the basis for the further study of the function of pm-TOR in growth and development in Pinctada martensii.