HIV-1B'亚型毒株感染者Nef蛋白氨基酸序列变异分析  

Analysis of amino acid sequence variation of Nef protein derived from HIV-1 B' infected individuals

作　　者：陈燕丽[1] 胡园园[1] 郝金娟[1] 任莉[1] 邵一鸣 洪坤学[1] 

机构地区：[1]中国疾病预防控制中心性病艾滋病预防控制中心传染病预防控制国家重点实验室,北京102206

出　　处：《中国热带医学》2015年第4期397-401,共5页China Tropical Medicine

基　　金：国家自然科学基金(No.31411130194);"十二五"传染病防治研究项目(No.2012ZX10001-008)

摘　　要：目的分析HIV-1 B’亚型毒株Nef蛋白重要功能区及CTL表位氨基酸序列变异特征。方法从137例HIV-1感染者的血浆样本中提取病毒RNA,进行逆转录获得c DNA,再经巢式PCR扩增全长Nef基因并纯化测序。利用Bio Edit、Mega6.0软件分析所获得的Nef基因重要功能区的氨基酸变异,并比较所获得的Nef基因共享序列与我国B亚型Nef共享序列及国际B亚型Nef共享序列的CTL表位情况。结果 HIV-1 B’亚型毒株Nef蛋白N端豆蔻酰化信号区、蛋白酶加工区、酸性区、Pak结合区、Pxx P区等功能区氨基酸序列较为保守,但有3个功能区中存在变异率大于30%的氨基酸位点,其中长度可变区的21号密码子上的R被E/K/Q取代的变异率达56.21%(R21E 24.09%,R21K 19.71%,R21Q 12.41%),COPI结合区EE154-155的E154被K取代的变异率为32.85%,双亮氨酸基序Exxx LL160-165的S163被C取代率为30.66%。本研究所得的137条Nef蛋白的共享序列的CTL表位与我国HIV-1 B亚型的共享序列CTL表位一致,而与国际B亚型共享序列相比有两个肽段表位的氨基酸发生了变异。结论 HIV-1 B’亚型毒株Nef蛋白多数重要功能区及CTL表位的氨基酸序列较保守,但有3个功能区存在变异率大于30%的氨基酸位点,这种特性可能影响病毒致病作用。Objective To study the characteristics of amino acid variation of important functional domains and CTLepitopes of Nef protein derived from HIV-1 subtype B’infected individuals. Methods Viral RNAs were extracted from theplasma of 137 HIV-1 infected individuals and their c DNAs were synthesized through reverse transcription. The full-length nefgene was amplified by nested-PCR and then sequenced directly after purification. Bioedit and Mega 6.0 softwares were used toanalyze the amino acid variation of important functional domains and CTL epitopes of these nef sequences by comparison withHIV-1 subtype B’consensus nef and international HIV-1 subtype B consensus nef. Results The N myristoylation signal,protease processing site,acidic region,Pak binding region,Pxx P region were relatively conserved in HIV-1 subtype B’Nefprotein,while three Nef domains with amino acid variation greater than 30% were observed,among them,R21E/K/Qsubstitutions in length variable region reaches 56.21%（R21E 24.09%,R21 K 19.71%,R21 Q 12.41%）,and the E154 Ksubstitution in the region of COPI binding（EE154-155）and S163 C substitution in the dileucine motif（Exxx LL160-165）were32.85% and 30.66%,respectively. In addition,CTL epitopes of the derived Nef proteins were highly-conserved and were inaccordance with that of HIV- 1 subtype B’consensus nef,but differ in two epitopes with international HIV- 1 subtype Bconsensus nef. Conclusion The results indicate that most of the important functional domains and CTL epitopes of HIV-1subtype B’Nef protein were relatively conserved,though three Nef domains with amino acid variation greater than 30% wereobserved,which might be relevant to the pathogenesis of HIV-1.

关 键 词：HIV-1 NEF蛋白 功能区 CTL表位 

分 类 号：R512.91[医药卫生—内科学]