甘蔗花叶病毒(SCMV)种群结构分析  

The population structure of Sugarcane mosaic virus( SCMV)

作　　者：郑艳茹[1] 翟玉山[1] 邓宇晴[1] 成伟[1] 程光远[1] 杨永庆[1] 徐景升[1] 

机构地区：[1]福建农林大学农业部福建甘蔗生物学与遗传改良重点实验室,福建福州350002

出　　处：《福建农林大学学报（自然科学版）》2016年第2期135-140,共6页Journal of Fujian Agriculture and Forestry University:Natural Science Edition

基　　金：国家高技术研究发展计划项目(2013AA102604);国家自然科学基金项目(31171605;31371688)

摘　　要：针对已公布的18个甘蔗花叶病毒(SCMV)全基因组序列,利用MEGA 5.1分析了其11个蛋白(P1、HC-Pro、P3、6K1、CI、6K2、VPg、NIa-Pro、Nib、CP-C和多聚蛋白)编码基因所受的选择压,并结合其编码蛋白的功能,预测了部分基因在SCMV进化过程中的角色和变异位点.结果显示:P1和CP-N端的变异性程度较大,P1蛋白多样性最高;CP-C端变异性和多样性均较低;PIPO受到的选择压最小,但多样性最低,可能是由于PIPO与P3共用一段编码序列.来源于甘蔗的SCMV多聚蛋白的第2 853、2 897和2 904个氨基酸位点(在CP中部)分别为T、R和E,而来源于玉米的SCMV多聚蛋白对应的氨基酸位点分别为S、K和D,表明这3个位点具有寄主依赖性.The population structure and phylogenetic analysis were conducted on 18 fully sequenced Sugarcane mosaic virus（ SCMV）isolates. MEGA 5. 1 was applied to evaluate the selective pressure of 11 genes encoding regions,i. e. P1,HC-Pro,P3,6K1,CI,6K2,VPg,NIa-Pro,Nib,CP-C and polyprotein. Basing on the known function of genes from Potyvirus genome,we predicted the potential roles and nucleotide substitutions sites of the 11 genes. The results were as following： P1 and N terminal of CP（ CP-N） demonstrated the maximum variability while P1 showed the highest diversity among the tested SCMV isolates. However,the C terminal of CP（ CP-C） displayed the minimum variability and diversity. PIPO was under the lowest selective pressure and diversity,which may be attributed to PIPO sharing the same encoding region with P3. Also,the 2 853 th,2 897 th and 2 904 th amino-acid residues of the polyprotein from SCMV sugarcane isolates presented different patterns comparing to the isolates from maize. The corresponding aminoacid residues were T,R and E in the polyprotein of SCMV isolated from sugarcane,but S,K and D for those isolated from maize,respectively. The distinguished pattern of these three amino-acid residues sites demonstrated strong host preference.

关 键 词：甘蔗花叶病毒 种群结构 选择压力 

分 类 号：Q931[生物学—微生物学]