摘要
本文报道１９８７年从广西病人血清中分离的登革２型（Ｄ２）病毒Ｄ２－４３株和１９８５年从海南病人血清中分离的Ｄ２－０４株乳鼠致病性的差异与基因变化的关系。结果表明Ｄ２－４３株对乳鼠致病，Ｄ２－０４株不致病。Ｄ２－４３株和Ｄ２－０４株Ｃ到ＮＳ１基因的读码框架基本相同，均由３３８１核苷酸组成，编码氨基酸总数１１２７。包含三个结构蛋白Ｃ．ＰｒＭ（Ｍ）、Ｅ和一个非结构蛋白ＮＳ１。该两株病毒核苷酸序列同源性为９３．８％，氨基酸序列的类似性为９１．３％。Ｃ和Ｅ基因同源性为９５．０％～９５．８％，ＮＳ１基因为９２．２％，Ｍ基因为８６．７％，两株之间核苷酸序列的主要差异是在Ｍ基因。两株病毒的Ｃ－ＮＳ１基因与国际参考毒株比较，４３株与ＪＡＭ株类侧性最高，其次是ＮＧＣ株，与Ｓ１株类似性最小。而０４株只有Ｃ、Ｅ和ＮＳ１与ＪＡＭ株最高，ＰｒＭ（Ｍ）都与ＮＧＣ株最高。４３株与０４株的Ｍ基因相比较，０４株的ＰｒＭ（Ｍ）基因的同源性低于４３株，说明两株与国际参考毒株比较，主要差异也在Ｍ基因，乳鼠致病性差异可能与Ｍ基因变化有关。
2-43 strain isolated from Guangxi in 1987,was pathogenetic to suckling mice,while D2-04 strain isolatdfrom Hainan in 1985,was not pathogenetic.The nucleotides and tbeir corresponding amino acid sequences of struc-tural protein C,PrM(M),E and non-structural protein NS1 gene of the two dengue-2 virus strains were analyzedand also compared with dengue-2 reference virus strains(JAM,NGC,S1)in homology of nucleotide sequence,gly-cosylation site,cysteine residue,cleavage site,hydropathy profiles of protein.The results showed that a open reading frame of C to NS 1 genes of D2-43 and D2-04 strains is identical,andcomposed of 3381 nucleotides and encoded a total number of 1127 amino acids. The number and position of glycosy-latfon site and conserved cysteine residue,hydropathy profiles and cleavage site of protein were identical too,butsome differences were revealed between D2-43 and D2-04.The homology of nucleotide sequeuce is 93.3%and thesimilarity of amino acid sequence is 91.3%。 In further comparison,we found that the homology of C,PrM(M),Eand NS1 gene of D2-43 and D2-04 strains revealed 95.0%,90.1%,86.7%,95.8%,92.2%respectively. The re-sults indicated C and E gene are the most conserved,M gene is most variable.The main difference is the changes ofM gene between D2-43 and D2-04 stranis.When D2-43 and D2-04 strain were compared with other dengue-2 virus reference strains in amino acid se-quence,we found that there is variable sequence at 151 ～ 240 position,is corresponding to PrM(M)region.The re-sults showed the changes of PrM(M)gene have caused the changes of amino acids. Which may relate to differencesof suckling mice pathogenesis.
出处
《中华微生物学和免疫学杂志》
CSCD
北大核心
1994年第5期296-299,共4页
Chinese Journal of Microbiology and Immunology
