广州检出星状病毒4型的全基因组序列测定及分析

目的 探讨广州地区儿童感染的星状病毒基因组分子结构特点和基因型.方法 参考GenBank上的星状病毒基因组设计分段扩增引物,进行RT-PCR分段扩增星状病毒基因组,克隆于T载体上,序列测定,用Clustal W和DNAStar软件分析基因组序列.结果 星状病毒HASTVgz01全基因组为6721 bp,提交到GenBank上的序列号为DQ344027,其中5＇端非编码区（5＇UTR）长82bp,3＇端非编码区末端长81 bp,病毒基因组编码区全长6558个核苷酸,分别编码ORF1a、ORF1b、ORF2,ORF1a基因长2763 bp（83～2845 nt）,ORF1b基因长1557bp（2785～4332 nt）,其中ORF1a、ORF1b两基因有71个核苷酸的重叠区;ORF2全长2316 nt,位于基因组中4325～6640 nt.ASTVgz01与GenBank中8种基因型星状病毒的ORF2基因氨基酸序列同源性比较发现,HASTVgz01与4型的同源性为93%,其他的同源性在61%～70%之间.结论 广州地区儿童腹泻感染的星状病毒HASTVgz01全基因组为6721bp,GenBank序列号为DQ344027,HASTVgz01与4型星状病毒的ORF2基因氨基酸序列比较同源性为最高,确认HASTVgz01是4型星状病毒.

The complete genomic sequence analysis of genotype 4 human astrovirus HASIVgz01 in Guangzhou

To study the genomic molecular organization and genotype of human astrovims in infected infants in Guangzhou,China.Methods Primers were designed on the basis of the genomic sequence of astrovirus in the GenBank,and the astrovirua genome was amplified by RT-PCR.The PCR-preducts were cloned to T vector and sequenced,the genomic nucleotide sequences were analyzed with the programs Clustal W and DNAS- tar.Results The full genornic length of HASTVgz01 is 6721 bp and the open reading frames(ORFs)are 6558 bp.The 5'and 3'UTR are 82 and 81 nucleotides long,respectively.The genome is organized in three OBFs: ORF1a,ORFlb and ORF2.The 5'-proximal ORF1a starts at nucleotide 83 and extends to nucleotide 2845. ORF1b(nt 2785 to nt 4332)overlaps ORF1a by 71 nucleotides.The 3'-proximal ORF2 begins at nucleotide 4325 and terminates at nucleotide 6540 and ORF2 is about 2316 bp long and compared with those of astrovirus in GenBank and revealed that it has the highest homology with serotype 4(93%).Homology with other serotypes ranges between 61% and 70%.Conclusion The complete nucleotide sequence of astrovirus HASTVgz01 detect- ed in Guangzhou,China is 6721 bp long,with GenBank accession NO.DQ344027.Comparison of the ORF2 of astrovirus HASTVgz01 with the known sequences of types 1-8 shows it had the highest homology with serotype 4 (93%).Comparative sequence analysis of the HASTVgz01 ORF2 with reported human astrovirna sequences re- vealed that this pathogen belongs to genatype(serotype)4.