A molecular switch required for retrovirus assembly participates in the hexagonal immature lattice
A molecular switch required for retrovirus assembly participates in the hexagonal immature lattice
复制标题
DOI：
10.1038/emboj.2008.71
复制
发表时间：
2008-05-07
期刊：
影响因子：
11.4
通讯作者：
Vogt, Volker M.
中科院分区：
文献类型：
--
作者：
Phillips, Judith M.;Murray, Paul S.;Vogt, Volker M.
在劳氏肉瘤病毒（RSV）Gag蛋白中，紧邻CA结构域上游的p10结构域的25个氨基酸残基对于未成熟颗粒的形成是必需的。我们在该区域进行了系统的诱变，发现体外组装所需的氨基酸侧链与先前描述的晶体结构中参与p10-CA二聚体界面的氨基酸侧链之间具有良好的相关性。我们引入了外源性半胱氨酸残基，预计形成二硫键的二聚体界面。在未成熟颗粒氧化后，形成二硫键连接的Gag六聚体，这意味着p10参与并稳定未成熟的Gag六聚体。这是两个不同Gag结构域之间关键相互作用的第一个例子。RSV未成熟六聚体的分子建模表明CA的N-末端结构域必须相对于鼠白血病病毒成熟六聚体扩展以容纳p10接触;这种扩展与最近未成熟人类免疫缺陷病毒颗粒的冷冻断层扫描结果惊人相似。
In the Rous sarcoma virus (RSV) Gag protein, the 25 amino-acid residues of the p10 domain immediately upstream of the CA domain are essential for immature particle formation. We performed systematic mutagenesis on this region and found excellent correlation between the amino-acid side chains required for in vitro assembly and those that participate in the p10-CA dimer interface in a previously described crystal structure. We introduced exogenous cysteine residues that were predicted to form disulphide bonds across the dimer interface. Upon oxidation of immature particles, a disulphide-linked Gag hexamer was formed, implying that p10 participates in and stabilizes the immature Gag hexamer. This is the first example of a critical interaction between two different Gag domains. Molecular modeling of the RSV immature hexamer indicates that the N-terminal domains of CA must expand relative to the murine leukaemia virus mature hexamer to accommodate the p10 contact; this expansion is strikingly similar to recent cryotomography results for immature human immunodeficiency virus particles.