摘要
目的 :测定和分析我国登革 2型病毒福建株 (FJ 11)基因组非编码区 (NCR)序列 ,为探讨其结构特征与功能的关系提供依据。方法 :从登革 2型病毒感染的C6/36细胞中提取总RNA ,采用RACE法扩增病毒基因组 5′和 3′端片段 ,分别将其克隆至pGEM T载体 ,挑取阳性克隆进行序列测定 ;利用RNAdraw软件对非编码区二级结构进行预测。结果与结论 :我国登革 2型病毒FJ 11株基因组 5′和 3′非编码区长度分别为 96nt和 4 5 4nt,具有黄病毒共有的保守序列和二级结构。与登革 2型病毒美洲基因型比较显示 ,5′NCR第 69位核苷酸的改变对其二级结构有影响 ;3′NCR端约 70nt能形成相同的保守结构 ,而前 380nt呈现多处核苷酸的差异而导致两者预测的二级结构差别较大 。
Objective: To determine and analyze the sequence s of the genome noncoding regions (NCR) of dengue type 2 virus Fujian strain (FJ 11) isolated in 1999 and to provide information about the relationship between viral NCRs and their functi o ns. Methods: With total RNA extracted from C6/36 cells infected by FJ11 virus s train, the specific fragments of viral 5~{!d~} and 3~{!d~} NCRs were amplified by RACE a nd cloned into pGEMT vectors, respectively.Positive clones were identified and t he inserted fragments were sequenced. The secondary structures of 5~{!d~} and 3~{!d~} NC R were predicted with RNAdraw software. Results and Conclusions: ~{!<~}WTBZ ~{!=~} The 5~{!d~} and 3~{!d~} N CRs of FJ11 strain are 96 and 454?nt in length,respectively and have the comm onl yconserved sequences and secondary structures of flaviviruses. Comparing with A merican genotype,the differences at nucleotide 69 of 5~{!d~} NCR had infl uence on the predicted secondary structure. A conserved region of 70?nt was fou n d at the 3~{!d~}terminus, which formed a characteristic stemloop structure. Howeve r, a striking size and sequence heterogenecity was observed in the 380?nt upstr eam re gion, which might be of great importance to the replication of dengue virus geno me RNA.
出处
《军事医学科学院院刊》
CSCD
北大核心
2001年第3期166-170,共5页
Bulletin of the Academy of Military Medical Sciences
基金
国家自然科学基金资助项目 ( 39770 0 36 )