Unmyristylated Moloney murine leukemia virus Pr65gag is excluded from virus assembly and maturation events
Unmyristylated Moloney murine leukemia virus Pr65gag is excluded from virus assembly and maturation events
复制标题
未肉豆蔻酰化莫洛尼鼠白血病病毒 Pr65gag 被排除在病毒组装和成熟事件之外
作者：
A. Schultz;A. Rein
莫洛尼鼠白血病病毒（MuLV）的gag前体多蛋白通常通过N-末端甘氨酸的肉豆蔻酰化进行修饰。先前的工作表明，Pr 65 gag缺乏肉豆蔻基化位点，不与细胞膜结合或组装成病毒颗粒。我们现在报告说，它也不裂解成成熟的gag裂解产物的细胞内，它作为一个免费的65千道尔顿的单体在洗涤剂的细胞提取物含有0.3 M NaCl沉淀。即使当含有突变体的细胞被野生型MuLV有效感染时，突变体Pr 65 gag也不被加工成切割产物，并且不被掺入这些细胞产生的病毒体中。因此，突变gag分子似乎不能参与自组装和成熟的正常过程。我们认为肉豆蔻酸酯介导的膜结合是MuLV组装的重要第一步。这种关联也可能在MuLV的萌芽中发挥作用。
The gag precursor polyprotein of Moloney murine leukemia virus (MuLV) is normally modified by myristylation of the N-terminal glycine. Previous work showed that the Pr65gag lacking the myristylation site does not associate with cellular membranes or assemble into virus particles. We now report that it also is not cleaved to the mature gag cleavage products within the cell and that it sediments as a free 65-kilodalton monomer in detergent-free cell extracts containing 0.3 M NaCl. Even when the cells containing the mutant are productively infected with wild-type MuLV, the mutant Pr65gag is not processed into cleavage products and is not incorporated into the virions produced by these cells. Thus, the mutant gag molecules seem unable to participate in the normal processes of self-assembly and maturation. We propose that myristate-mediated membrane association is an essential first step in MuLV assembly. This association may also play a role in budding of MuLV.