Freed E O, Orenstein J M, Buckler-White A J, Martin M A
Laboratory of Molecular Microbiology, National Institute of Allergy and Infectious Diseases, Bethesda, Maryland 20892.
J Virol. 1994 Aug;68(8):5311-20. doi: 10.1128/JVI.68.8.5311-5320.1994.
The matrix protein of human immunodeficiency virus type 1 is encoded by the amino-terminal portion of the Gag precursor and is postulated to be involved in a variety of functions in the virus life cycle. To define domains and specific amino acid residues of the matrix protein that are involved in virus particle assembly, we introduced 35 amino acid substitution mutations in the human immunodeficiency virus type 1 matrix protein. Using reverse transcriptase and radioimmunoprecipitation analyses and transmission electron microscopy, we assessed the mutants for their ability to form virus particles and to function in the infection process. This study has identified several domains of the matrix protein in which single amino acid substitutions dramatically reduce the efficiency of virus particle production. These domains include the six amino-terminal residues of matrix, the region of matrix between amino acids 55 and 59, and the region between amino acids 84 and 95. Single amino acid substitutions in one of these domains (between matrix amino acids 84 and 88) result in a redirection of the majority of virus particle formation to sites within cytoplasmic vacuoles.
1型人类免疫缺陷病毒的基质蛋白由Gag前体的氨基末端部分编码，据推测在病毒生命周期中参与多种功能。为了确定基质蛋白中参与病毒粒子组装的结构域和特定氨基酸残基，我们在1型人类免疫缺陷病毒基质蛋白中引入了35个氨基酸替代突变。通过逆转录酶和放射免疫沉淀分析以及透射电子显微镜，我们评估了这些突变体形成病毒粒子的能力以及在感染过程中的功能。这项研究确定了基质蛋白的几个结构域，其中单个氨基酸替代会显著降低病毒粒子产生的效率。这些结构域包括基质的六个氨基末端残基、氨基酸55至59之间的基质区域以及氨基酸84至95之间的区域。这些结构域之一（基质氨基酸84至88之间）的单个氨基酸替代导致大多数病毒粒子形成重新定位到细胞质液泡内的位点。
