农业生物技术学报2012，Vol.20Issue(4)：426-435,10.DOI:10.3969/j.issn.1674-7968.2012.04.012
鲤CC型趋化因子CCL-C5a样基因的克隆、组织表达与进化分析
Cloning, Tissue Expressions and Evolutional Analysis of Cyprinus carpio CC chemokine CCL-C5a-like Gene
摘要
Abstract
Chemokines belong to a family of chemotactic cytokines which are involved in activation and migration of leukocytes. They play important roles in the innate immune system of fish species. The CC chemokines are one of the biggest superfamilies of chemokines. To understand tissue expression, evolution models and immune regulation mechanism of Cyprinus carpio CC chemokines, we selected a member of CC chemokines, CCL-C5a, for further study. In this study, a full-length cDNA of CC chemokine CCL-C5a-like gene was amplified in C. carpio spleen by RACE method (GenBank accession No. JQ026408). The full-length cDNA was 830 bp in size, with 174 bp 5'UTR, 296 bp 3'UTR and 360 bp open reading frame (ORF). The ORF encoded a protein of 119 amino acids. Functional domain analysis showed that this protein contained signal peptide and conserved chemokine structure. Gene Ontology annotation indicated that this protein was involved in the biological process of immune cell migration. CCL-C5a was widely expressed in brain, skin, muscle, head kidney, body kidney, intestine, gill and heart and mainly in spleen and liver. After lipopolysaccharide stimulation, the expression of CCL-C5a showed significantly increase in peripheral blood leukocytes and head kidney leukocytes. The deduced amino acid sequence of C. carpio CCL-C5a shared high identity with other seven species, which was from 37% to 61%, and the highest was 61% with Danio rerio. Adaptive evolution analysis revealed that the Ka/Ks of CCL-C5a bewteen C. carpio and Danio rerio was less than 1, indicating that CCL-C5a was under negative selection pressure in the evolutionary process offish species. We conclude that C. carpio CCL-C5a are principally expressed in immune organs and up-regulated after lipopolysaccharide stimulation and that this gene is under negative selection pressure in fish species. These results indicate that C. carpio CCL-C5a may be a immune-relevant gene.关键词
鲤/免疫反应/CC趋化因子/克隆/脂多糖/序列保守性Key words
Cyprinus carpio/ Immune response/ CC chemokines/ Clone/ Lipopolysaccharide/ Sequence conservation引用本文复制引用
汪金兔,李炯棠,万玉美,冀培丰,崔润滋,张研,蒋丽,徐鹏,孙效文..鲤CC型趋化因子CCL-C5a样基因的克隆、组织表达与进化分析[J].农业生物技术学报,2012,20(4):426-435,10.基金项目
国家高技术研究发展计划(863)项目(No.2011AA100401)、公益性行业(农业)科研专项项目(No.200903045)和中国水产科学研究院本级基本科研业务费(No.2011C016) （863）
