HIV-1 protease dimer interface mutations that compensate for viral reverse transcriptase instability in infectious virions
HIV-1 protease dimer interface mutations that compensate for viral reverse transcriptase instability in infectious virions
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DOI：
10.1016/j.jmb.2007.06.073
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发表时间：
2007-09-14
影响因子：
5.6
通讯作者：
Menendez-Arias, Luis
中科院分区：
文献类型：
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作者：
Olivares, Isabel;Mulky, Alok;Menendez-Arias, Luis
人类免疫缺陷病毒I型（HIV-1）基因组中编码的成熟酶（蛋白酶（PR）、逆转录酶（RT）和整合酶（IN））来源于大聚蛋白（Gag-Pol）的蛋白水解加工。Gag-Pol加工由病毒PR催化，其作为同二聚体是有活性的。HIV-1 RT作为异二聚体（p66/p51）发挥功能，分别由560和440个氨基酸残基的亚基组成。这两个亚基具有相同的氨基酸序列，但p51缺乏120个残基，这些残基在病毒成熟期间被HIV-1 PR去除。虽然p66是催化亚基，但p51具有主要的结构作用。影响p66/p51（即F130 W）稳定性的氨基酸取代对病毒适应性具有有害影响。以前，我们发现F130 W的作用是由p51介导的，并且可以通过突变T58 S来补偿。在研究补偿突变出现的动力学时，我们观察到在T58 S/F130 W突变之前，在含有RT取代F130 W的HIV克隆中选择了病毒PR编码区中的突变。鉴定的PR突变（G94 S和T96 S）提高了F130 W突变病毒的复制能力。通过使用反式互补试验，我们证明Trp 130引起的p66/p51异源二聚体稳定性的丧失可归因于RT对病毒PR降解的敏感性增加。携带突变G94 S或T96 S的重组HIV-1 PR显示出降低的二聚体稳定性和降低的催化效率。这些结果与显示PR二聚化界面中两个残基的位置的晶体学数据一致。(C)2007爱思唯尔有限公司保留所有权利。
Mature enzymes encoded within the human immunodeficiency virus type I (HIV-1) genome (protease (PR), reverse transcriptase (RT) and integrase (IN)) derive from proteolyfic processing of a large polyprotein (Gag-Pol). Gag-Pol processing is catalyzed by the viral PR, which is active as a homodimer. The HIV-1 RT functions as a heterodimer (p66/p51) composed of subunits of 560 and 440 amino acid residues, respectively. Both subunits have identical amino acid sequence, but p51 lacks 120 residues that are removed by the HIV-1 PR during viral maturation. While p66 is the catalytic subunit, p51 has a primarily structural role. Amino acid substitutions affecting the stability of p66/p51 (i.e. F130W) have a deleterious effect on viral fitness. Previously, we showed that the effects of F130W are mediated by p51 and can be compensated by mutation T58S. While studying the dynamics of emergence of the compensatory mutation, we observed that mutations in the viral PR-coding region were selected in HIV clones containing the RT substitution F130W, before the imposition of T58S/ F130W mutations. The PR mutations identified (G94S and T96S) improved the replication capacity of the F130W mutant virus. By using a transcomplementation assay, we demonstrate that the loss of p66/p51 heterodimer stability caused by Trp130 can be attributed to an increased susceptibility of RT to viral PR degradation. Recombinant HIV-1 PRs bearing mutations G94S or T96S showed decreased dimer stability and reduced catalytic efficiency. These results were consistent with crystallographic data showing the location of both residues in the PR dimerization interface. (C) 2007 Elsevier Ltd. All rights reserved.