Potent inhibition of HIV-1 replication by a Tat mutant.
Potent inhibition of HIV-1 replication by a Tat mutant.
复制标题
Tat 突变体有效抑制 HIV-1 复制。
DOI：
10.1371/journal.pone.0007769
复制
发表时间：
2009-11-10
期刊：
影响因子：
3.7
通讯作者：
Harrich D
中科院分区：
文献类型：
--
作者：
Meredith LW;Sivakumaran H;Major L;Suhrbier A;Harrich D
在此，我们描述了一个突变的两外显子HIV-1达特蛋白，称为Nullbasic，有效地抑制多个步骤的HIV-1复制周期。通过用甘氨酸/丙氨酸残基替换野生型达特的整个富含甘氨酸的碱性结构域来产生Nullbasic。与类似突变的单外显子达特突变体一样，Nullbasic对Tat依赖性反式激活表现出反式显性负效应。然而，与以前报道的突变体不同，我们发现Nullbasic还强烈抑制未剪接和单剪接病毒mRNA的表达，这种活性可能是由HIV-1 Rev的再分布和功能抑制引起的。此外，由表达Nullbasic的细胞产生的HIV-1病毒粒子严重降低了感染性，这是由于病毒粒子进行逆转录的能力降低而导致的缺陷。对反式激活、Rev依赖性mRNA转运和逆转录的这些抑制作用的组合意味着组成性表达Nullbasic的容许细胞对HIV-1的扩散感染具有高度抗性。因此，Nullbasic及其活性为开发针对HIV-1感染多个阶段的有效抗病毒疗法提供了潜在的见解。
Herein we describe a mutant of the two-exon HIV-1 Tat protein, termed Nullbasic, that potently inhibits multiple steps of the HIV-1 replication cycle. Nullbasic was created by replacing the entire arginine-rich basic domain of wild type Tat with glycine/alanine residues. Like similarly mutated one-exon Tat mutants, Nullbasic exhibited transdominant negative effects on Tat-dependent transactivation. However, unlike previously reported mutants, we discovered that Nullbasic also strongly suppressed the expression of unspliced and singly-spliced viral mRNA, an activity likely caused by redistribution and thus functional inhibition of HIV-1 Rev. Furthermore, HIV-1 virion particles produced by cells expressing Nullbasic had severely reduced infectivity, a defect attributable to a reduced ability of the virions to undergo reverse transcription. Combination of these inhibitory effects on transactivation, Rev-dependent mRNA transport and reverse transcription meant that permissive cells constitutively expressing Nullbasic were highly resistant to a spreading infection by HIV-1. Nullbasic and its activities thus provide potential insights into the development of potent antiviral therapeutics that target multiple stages of HIV-1 infection.