Lu Y L, Bennett R P, Wills J W, Gorelick R, Ratner L
Department of Medicine, Washington University, St. Louis, Missouri 63110, USA.
J Virol. 1995 Nov;69(11):6873-9. doi: 10.1128/JVI.69.11.6873-6879.1995.
Incorporation of Vpr into human immunodeficiency virus type 1 (HIV-1) virions is mediated by the Gag protein, independently of other viral components. We have coexpressed Vpr and Gag constructs in a vaccinia virus expression system in order to map the region of Gag involved in Vpr packaging. Deletion of the carboxyl-terminal p6 region of Gag impaired the ability of Gag to package Vpr. To confirm the role of p6 in Vpr packaging, Rous sarcoma virus (RSV)-HIV chimeras containing HIV-1 p6 were constructed. Although RSV Gag does not package Vpr into virus particles, a chimera containing HIV-1 p6 is sufficient for Vpr incorporation. To map the region of p6 involved in Vpr packaging, a series of p6 point mutations and deletion mutations was analyzed. Mutations in the N-terminal p6 proline-rich domain, for which preliminary evidence shows a marked decrease in virion incorporated RNA, did not affect Vpr incorporation. Deletion of residues 1 to 31 of HIV-1 p6 did not affect Vpr packaging, but residues 35 to 47, including an (LXX)4 domain, were required for Vpr incorporation into virus particles.
Vpr整合到人免疫缺陷病毒1型（HIV-1）病毒粒子中是由Gag蛋白介导的，独立于其他病毒成分。我们在痘苗病毒表达系统中共表达了Vpr和Gag构建体，以确定参与Vpr包装的Gag区域。删除Gag的羧基末端p6区域会损害Gag包装Vpr的能力。为了证实p6在Vpr包装中的作用，构建了含有HIV-1 p6的劳斯肉瘤病毒（RSV）-HIV嵌合体。尽管RSV Gag不会将Vpr包装到病毒颗粒中，但含有HIV-1 p6的嵌合体足以使Vpr整合。为了确定p6中参与Vpr包装的区域，分析了一系列p6点突变和缺失突变。N末端富含脯氨酸的p6结构域中的突变，初步证据表明病毒粒子中掺入的RNA显著减少，但不影响Vpr的掺入。删除HIV-1 p6的1至31位残基不影响Vpr包装，但Vpr整合到病毒颗粒中需要35至47位残基，包括一个（LXX）4结构域。
