大黄鱼CCTα基因的克隆及其表达量随稚鱼生长发育的变化

MOLECULAR CLONING AND GENETIC ONTOGENY OF CCTα DURING THE DEVELOPMENT OF LARGE YELLOW CROAKER LARVAE(LARIMICHTHYS CROCEA)

研究旨在克隆大黄鱼磷脂酰胆碱合成关键基因磷脂酰胆碱胞苷转移酶α(CCTα)基因全长,并检测其表达量随稚鱼生长发育的变化。利用同源克隆技术和RACE技术从大黄鱼肝脏中成功扩增出CCTα的全长。同时应用real-time PCR法检测不同日龄大黄鱼稚鱼CCTα的表达变化。序列分析表明,CCTα全长2419 bp(Gen Bank登录号:KF006239.1),包括273 bp的5'端非编码区,1107 bp的开放阅读框,1010 bp的3'端非编码区,共编码369个氨基酸。系统进化树分析表明,相比其他物种,大黄鱼CCTα基因与红鳍东方鲀的亲缘关系较近。定量结果表明,孵化后,大黄鱼仔稚鱼CCTα的表达量随日龄的变化先显著升高,在15日龄时达到最大值,随后显著下降并趋于平稳,CCTα基因表达量的变化趋势与大黄鱼稚鱼消化系统的发育密切相关。

In the present study, the full length of CCTα (CTP: choline phosphate cytidylyltranferase) cDNA from largeyellow croaker (Larimichthys crocea) was obtained by homology-based cloning and rapid amplification of cDNA ends(RACE) techniques. Sequence analysis showed that the full length of CCTα cDNA (GenBank accession No.KF006240.1) was 2419 bp, which consisted of 1107 bp open-reading frame (ORF) encoding 369 amino acids, a 273 bp5'-untranslated region (5'UTR) and a 1010 bp 3'-untranslated region (3'UTR). Phylogenetic tree analysis showed thatthe CCTα gene of large yellow croaker had a closer relationship with Takifugu rubripes than others. The expression ofCCTα increased significantly at first, and then decreased, and peaked at 15 day after hatching. The genetic ontogeny ofCCTα was related to the development of large yellow croaker digestive system.