Mutagenesis of the putative alpha-helical domain of the Vpr protein of human immunodeficiency virus type 1: effect on stability and virion incorporation.
Mutagenesis of the putative alpha-helical domain of the Vpr protein of human immunodeficiency virus type 1: effect on stability and virion incorporation.
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人类免疫缺陷病毒 1 型 Vpr 蛋白的假定 α 螺旋结构域的诱变：对稳定性和病毒粒子掺入的影响。
DOI：
10.1073/pnas.92.9.3794
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发表时间：
1995
影响因子：
11.1
通讯作者：
Srinivasan,A
中科院分区：
文献类型：
--
作者：
Mahalingam,S;Khan,SA;Murali,R;Jabbar,MA;Monken,CE;Collman,RG;Srinivasan,A
vpr是人类免疫缺陷病毒1型（HIV-1）的辅助基因之一，在相关的HIV-2/猿猴免疫缺陷病毒慢病毒中是保守的。Vpr的独特之处在于它是唯一一种整合到病毒颗粒中的非结构蛋白。二级结构分析预测在Vpr的氨基末端（残基17-34）的两亲性α-螺旋结构域，其含有5个酸性残基和4个亮氨酸残基。为了评价螺旋结构域的特定残基对于病毒体掺入的作用，进行了该结构域的诱变。用脯氨酸取代任何单个酸性残基（Asp-17和Glu-21、-24、-25和-29），消除了Vpr的病毒粒子掺入，也改变了Vpr在细胞中的稳定性。保守取代谷氨酸残基的螺旋结构域与天冬氨酸残基导致Vpr的野生型的特点，无论是在稳定性和病毒体掺入，作为取代谷氨酰胺的酸性残基。相反，丙氨酸取代螺旋结构域的亮氨酸残基（残基20，22，23和26）消除Vpr的病毒体掺入功能。这些数据表明，酸性和疏水性残基和螺旋结构在这个区域是关键的Vpr的稳定性和其有效地纳入病毒样颗粒。
vpr is one of the auxiliary genes of human immunodeficiency virus type 1 (HIV-1) and is conserved in the related HIV-2/simian immunodeficiency virus lentiviruses. The unique feature of Vpr is that it is the only nonstructural protein incorporated into the virus particle. Secondary structural analysis predicted an amphipathic alpha-helical domain in the amino terminus of Vpr (residues 17-34) which contains five acidic and four leucine residues. To evaluate the role of specific residues of the helical domain for virion incorporation, mutagenesis of this domain was carried out. Substitution of proline for any of the individual acidic residues (Asp-17 and Glu-21, -24, -25, and -29) eliminated the virion incorporation of Vpr and also altered the stability of Vpr in cells. Conservative replacement of glutamic residues of the helical domain with aspartic residues resulted in Vpr characteristic of wild type both in stability and virion incorporation, as did substitution of glutamine for the acidic residues. In contrast, replacement of leucine residues of the helical domain (residues 20, 22, 23, and 26) by alanine eliminated virion incorporation function of Vpr. These data indicate that acidic and hydrophobic residues and the helical structure in this region are critical for the stability of Vpr and its efficient incorporation into virus-like particles.