我国登革3型病毒广西80-2株基因组全序列分析

对我国登革 3型病毒 80 2株基因组进行全序列测定 ,为了解其基因组结构与功能的关系提供依据 .根据登革 3型病毒H87株的序列设计并合成引物 ,应用RT PCR和RACE法 ,对 80 2株基因组RNA进行扩增、克隆测序后获得我国登革 3型病毒广西株基因组序列 .该株病毒基因组全长10 696nt ,不含poly(A)尾 ,4种碱基数分别为A :3 4 3 7,C :2 2 15,G :2 773 ,U :2 2 71.包含一个读码框架 ,自 95至 10 2 67位 ,共 10 170个碱基 ,编码 3 3 90个氨基酸 ,5′和 3′非编码区长度分别为 94nt和4 3 2nt.与H 87株比较 ,核苷酸和氨基酸序列同源性均在 99%以上 ,有 2 8个碱基发生改变 ,其中 2 6个碱基突变发生在读码框架内 ,碱基转换 18个 ,颠换 10个 ;碱基突变引起 14个氨基酸的改变 .80 2株与H87株病毒的基因组全序列同源性高 ,变异度小 .

Analysis of Complete Genomic Sequence of the Dengue Type 3 Virus 80-2 Strain Isolated from Guangxi in China

In order to understand the relationships between structures and functions of the genome,sequence of genome of dengue virus type 3 strain 80-2 was determined.Primers were designed and synthesized according to the sequence of strain H 87.By means of RT PCR and RACE,the complete genomic sequence of the dengue virus type 3 strain 80-2 was obtained.The viral genome in 10 696 nt in length.The nucleotide composition is A 3 437,C 2 215,G 2 773 and U 2 271.A large open reading frame begins at the first ATG in the position 95 nt to 97 nt and encodes 3 390 amino acids,leaving two non coding regions at the 5′ and 3′ ends.Both the similarities of the nucleotides and amino acids between strains 80-2 and H 87 are above 99%,respectively.14 of 28 nucleotide changes resulted in the amino acid changes,with 10 transversion and 18 transition.The result suggests that the nucleotide sequence of dengue virus type 3 is more conservative than those of other serotypes of dengue virus.