Soneoka Y, Kingsman S M, Kingsman A J
Department of Biochemistry, University of Oxford, United Kingdom.
J Virol. 1997 Jul;71(7):5549-59. doi: 10.1128/JVI.71.7.5549-5559.1997.
We have created two sets of substitution mutations in the Moloney murine leukemia virus (Mo-MuLV) matrix protein in order to identify domains involved in association with the plasma membrane and in incorporation of the viral envelope glycoproteins into virus particles. The first set of mutations was targeted at putative membrane-associating regions similar to those of the human immunodeficiency virus type 1 matrix protein, which include a polybasic region at the N terminus of the Mo-MuLV matrix protein and two regions predicted to form beta strands. The second set of mutations was created within hydrophobic residues to test for the production of virus particles lacking envelope proteins, with the speculation of an involvement of the membrane-spanning region of the envelope protein in incorporation into virus particles. We have found that mutation of the N-terminal polybasic region redirected virus assembly to the cytoplasm, and we show that tryptophan residues may also play a significant role in the intracellular transport of the matrix protein. In total, 21 mutants of the Mo-MuLV matrix protein were produced, but we did not observe any mutant virus particles lacking the envelope glycoproteins, suggesting that a direct interaction between the Mo-MuLV matrix protein and envelope proteins either may not exist or may occur through multiple redundant interactions.
我们在莫洛尼鼠白血病病毒（Mo-MuLV）基质蛋白中创建了两组替代突变，以确定与质膜结合以及病毒包膜糖蛋白掺入病毒颗粒所涉及的结构域。第一组突变针对的是类似于1型人类免疫缺陷病毒基质蛋白的假定膜结合区域，其中包括Mo-MuLV基质蛋白N端的一个多碱性区域以及预测会形成β链的两个区域。第二组突变是在疏水残基内产生的，以测试缺乏包膜蛋白的病毒颗粒的产生情况，推测包膜蛋白的跨膜区域参与了其掺入病毒颗粒的过程。我们发现N端多碱性区域的突变将病毒组装重新导向细胞质，并且我们表明色氨酸残基在基质蛋白的细胞内运输中也可能起重要作用。总共产生了21种Mo-MuLV基质蛋白突变体，但我们没有观察到任何缺乏包膜糖蛋白的突变病毒颗粒，这表明Mo-MuLV基质蛋白与包膜蛋白之间可能不存在直接相互作用，或者可能通过多种冗余相互作用发生。
