水稻南方黑条矮缩病毒湖南鼎城株系S10片段的基因组序列分析

运用RT-PCR技术克隆了水稻南方黑条矮缩病毒(southern rice black-streaked dwarf virus,SRBSDV)湖南鼎城株系的基因组S10片段(SRBSDV-HuNDCS10),并对其全序列进行了测定和生物信息学分析。结果显示,SRBSDV-HuNDC S10片段全长为1797bp(登录号:JQ337964),含有1个ORF,编码557个氨基酸残基的衣壳蛋白,推测分子量约62.6kD,推测等电点为7.62,与已报道的广东、海南和云南分离物病毒的S10作比较,它们的核苷酸相似性分别为99.7%、99.0%和98.4%,氨基酸相似性分别为100.0%、99.5%和99.3%。对SRBSDV-HuNDCS10及部分Fijiviruses病毒对应片段在5’URT与3’URT存在的保守序列和互补序列进行了归纳,对其ORF编码的氨基酸序列进行了motif查找,得到该属(Fijiviruses)氨基酸序列的10个保守区段。此外,进行了糖基化位点、磷酸化位点及B细胞抗原表位预测,发现了3个可能的N端豆蔻酰基化位点,可能与病毒的侵染机制有关。

Sequence Analysis of Genome Segment S10 of Hunan Dingcheng Isolate of Southern Rice Black-Streaked Dwarf Virus

The full-length cDNA of the genome segment S10 of Dingcheng isolate of Southern Rice Black-Streaked Dwarf Virus was cloned and the complete nucleotide sequence was determined,as well as its bioinformatics analysis.Results show that the S10 is 1 797 bp(JQ337964),has an open reading frame(ORF),encodes a capsid protein containing 557 amino acid residues.Its molecular weight is about 62.6 kD and its isoelectric point is 7.62.Compared with other known viruses such as Guangdong isolates,Hainan isolates and Yunnan isolates,the nucleotide identities of S10 segment are 99.7%,99.0% and 98.4%,respectively,and their amino acid identities are 100.0%,99.5% and 99.3% respectively.Conservative sequence and complementary sequence in the 5’ URT and 3’ URT of SRBSDV-HuNDC S10 and corresponding segments of the Fijiviruses viruses were analyzed,and 10 conservative segment of Fijiviruses viruses were founded by searching the motif of amino acid sequence encoded by ORF.Moreover,the glycosylation sites,phosphorylation sites and B cell epitope were predicted.Three possible N-myristoylation sites were found,which may be involved in virus infection.