广东海洋大学学报Issue(1)：8-17,10.
鲤JAK2基因分子克隆及组织表达分析
Cloning and Expression Analysis of JAK2 Gene in Common Carp, Cyprinus carpio
摘要
Abstract
The full-length cDNA sequence of JAK2 gene from common carp, Cyprinus carpio is obtained by using homology cloning and RACE (rapid amplification of cDNA ends) PCR. The full cDNA sequence of common carp JAK2 in length is 4 639 bp, containing a 3 378 bp complete open reading frame (ORF) which encodes 1 125 amino acids, a 732 bp 5'-untranslated region (5'-UTR), and a 529 bp 3'-UTR, with corresponding molecular mass of 129.33 ku and the theoretical isoelectric point of 6.99. The identity and similarity of its amino acid sequence with the corresponding sequence of zebrafish are 89% and 95%, respectively. Bioinformatics analysis indicated that common carp JAK2 had a FERM domain, an SH2 domain, a pseudokinase domain, and a tyrosine kinase domain. These functional domains are conservative among JAKs from fish, amphibians and mammals, showing that they share similar functional mechanism. The spatial structural elements of carp JAK2 are predicted to includeα-helixes,β-sheets, and loops. Based on the phylogenetic tree of JAK2 generated by neighbor joining method in MEGA 4.0, it shows that each kind of JAKs forms a large monophyletic group, and that the JAK2 main-clade is a sister group to the JAK3 one, which means JAK2 is more closely related to JAK3. Moreover, all JAK2s from the teleost species, including common carp JAK2 in the present study, cluster together, then form the sister group with the second cluster consisting of all from amphibians and mammals. Thus, it is suggested that they should share a common ancestral gene of JAK2 and have remarkable orthologous relationships. The results of real-time quantitive PCR reveal that JAK2 and JAK3 genes are differentially expressed in various tissues of common carp at the level of mRNA. JAK2 is expressed in skin with the highest level, secondly in intestine, blood and brain, and expressed lowly in muscle, head kidney, heart, liver, gill and spleen.The expression level of carp JAK3 in spleen is particularly high, but relatively lower in other tissues. The results in this study have provided a basis for further evaluation on the regulation role of carp JAK2 in the JAK-STAT signaling pathway.关键词
鲤/JAK2/JAK3/基因克隆/组织表达分析Key words
Cyprinus carpio/JAK2/JAK3/gene cloning/tissue expression analysis分类
生物科学引用本文复制引用
付友,高谦,文春根,吴平,刘德立..鲤JAK2基因分子克隆及组织表达分析[J].广东海洋大学学报,2015,(1):8-17,10.基金项目
国家自然科学基金面上项目(31272666)；国家科技支撑计划课题(2012BAD25B0202)；国家自然科学基金面上项目(30871937) （31272666）
