猪圆环病毒3型Cap蛋白序列的生物信息学研究  

Bioinformatics Analysis of Cap Protein Sequences of Porcine Circovirus Type 3

作　　者：李周勉 邹亚文[1,2,3] 蒋一凡 胡意[1,2,3] 秦艺文 李萌[1,2,3] 湛洋 王东亮 王乃东 LI Zhoumian;ZOU Yawen;JIANG Yifan;HU Yi;QIN Yiwen;LI Meng;ZHAN Yang;WANG Dongliang;WANG Naidong(College of Veterinary Medicine,Hunan Agricultural Universily,Changsha 410128,China;Hunan Provincial Key Laboratory of Protein Engineering in Animal Vaccines,Changsha 410128,China;R&D Center of Animal Reverse Vaccinology of Hunan Prorince,Changsha 410128,China)

机构地区：[1]湖南农业大学动物医学院,长沙410128 [2]兽用蛋白质工程疫苗湖南省重点实验室,长沙410128 [3]兽用疫苗逆向创制湖南省工程研究中心,长沙410128

出　　处：《经济动物学报》2020年第1期9-16,共8页Journal of Economic Animal

基　　金：国家自然科学基金(31372406);湖南省自然科学基金面上项目(2018JJ2177);大学生研究性学习和创新性实验计划项目(SCX1836/201640307323);湖南农业大学校科学基金项目(17QN10)。

摘　　要：猪圆环病毒3型(PCV3)是一种在世界范围内分布较广泛的新型猪病毒,其发病机制尚不清楚。为系统分析PCV3 Capsid(Cap)蛋白序列和结构特点,收集Gen Bank登录的来自不同国家和地区的210条PCV3全基因组和Cap蛋白基因序列,筛选获得46株PCV3代表序列;采用生物信息学(Bio Edit和MAGE 6.0等)技术分析PCV3 Cap序列同源性、结构特点、系统进化和热点突变位点情况。结果表明:46株PCV3 Cap序列同源性为97.66%~100%,PCV3 Cap预测的8个B细胞和10个T细胞表位中均存在序列突变,其中B细胞抗原表位E(109~146位氨基酸)和T细胞抗原表位D(72~81位氨基酸)存在的突变位点数最多。研究发现26株属于PCV3a,20株属于PCV3b。PCV3与PCV2 Cap序列比较分析发现,PCV3 Cap在NLS区域内有6处突变(R11K、R12K、H26M、R27K、V31A和R34K);PCV3 Cap序列间比对分析发现,PCV3b Cap序列出现突变的几率(17/20,85%)高于PCV3a(19/26,73%)。而从临床表现有繁殖障碍和死胎的样品中检测出的PCV3序列均存在S77T和I150L突变位点;从伴有发热、肺炎的仔猪以及肺匀浆样本检测出的PCV3序列中均有R10K突变位点,这些特定的突变位点与临床症状的关系需后续深入研究。本研究结果为PCV3基因功能、进化、预防和控制等研究提供重要序列信息。Porcine circovirus type 3 is a new porcine virus already distributed worldwide,the pathogenesis of PCV3 remains unknown because isolation and continuous passage of PCV3 is failure in cell lines at present.In order to systematically analyze the sequence and structural characteristics of PCV3 Cap,210 PCV3 whole genome and the sequences of cap gene from different countries and regions published in Gen Bank were collected respectively,then 46 PCV3 representative sequences were screened,and the homology,structural features,phyletic evolution and hot spot mutation site of PCV3 Cap sequences were analyzed using bioinformatics technique(Bio Edit,MAGE 6.0 and etc.)in this study.The results showed that the homology of 46 PCV3 representative sequences was 97.66%-100%.Sequence mutations were found in 8 B cell epitopes and 10 T cell epitopes predicted by PCV3 Cap.Among them,B cell epitope E(109-146 aa)and T cell epitope D(72-81 aa)had the most mutation sites.26 PCV3 strains belonged to PCV3a which was prevalence in northern China and 20 PCV3 strains belonged to PCV3b.The comparative analysis of PCV3and PCV2 Cap sequences showed that PCV3 Cap had six mutations in NLS region(R11K,R12K,H26M,R27K,V31A and R34K);the mutation rate of PCV3 Cap sequence was higher(17/20,85%)than that of PCV3a(19/26,73%).Meanwhile,the results indicated that mutation sites(S77T and I150L)were related to reproductive disorders and stillbirths,and mutation site(R10K)was related to pneumonia and respiratory symptoms.The relationships between the certain mutation sites and clinical symptoms require further study.The results of this study lay a foundation for the study of pathogenicity of PCV3.

关 键 词：猪圆环病毒3型 CAP蛋白 氨基酸突变位点 生物信息学 

分 类 号：S852.651[农业科学—基础兽医学]