论文部分内容阅读
为了探索大豆花叶病毒(Soybean mosaic virus,SMV)SC7外壳蛋白(Coat protein,CP)基因序列与病毒致病性作用及其与美国株系的对应关系,本研究通过反转录-聚合酶链式反应(RT-PCR),克隆了我国SMV SC7株系的CP基因,并测定了其全序列。结果表明:CP基因长度为795bp,编码的CP蛋白为265个氨基酸。在致病性反应上,SC7的毒力比美国的毒株更强些。在分子水平上,CP基因核苷酸序列差异为4%~5%,编码的氨基酸序列差异为1%~2%。美国株系N端都存在与蚜传有关的保守基序DAG(Asp-Ala-Gl),但在SC7为DAD(Asp-AlaAsp)。将序列信息与SMV株系在鉴别寄主上的症状反应进行综合分析发现,CP基因的同源性与SMV在鉴别寄主上的致病性反应没有明显关系。
In order to explore the sequence and virulence of Coat protein (CP) gene of SC7 from Soybean mosaic virus (SMV) and its corresponding relationship with the American strain, this study was conducted by reverse transcription - polymerase chain CP gene of SMV SC7 strain in China was cloned by RT-PCR, and its full-length sequence was determined. The results showed that CP gene was 795bp in length and encoded 265 amino acids of CP protein. In pathogenic response, SC7 is more virulent than the U.S. strain. At the molecular level, the differences in the nucleotide sequence of the CP gene ranged from 4% to 5% and the amino acid sequences encoded varied from 1% to 2%. Aphid-specific conserved motif DAG (Asp-Ala-Gl) was found on the N-terminal of American lines, but DAD (Asp-AlaAsp) was found on SC7. A comprehensive analysis of the sequence information and symptom responses of SMV strains on differential hosts revealed that there is no significant relationship between the homology of CP genes and the pathogenic response of SMVs in identifying the host.