Evolutionary repair of HIV type 1 gp41 with a kink in the N-terminal helix leads to restoration of the six-helix bundle structure.
Evolutionary repair of HIV type 1 gp41 with a kink in the N-terminal helix leads to restoration of the six-helix bundle structure.
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DOI：
10.1089/0889222041524544
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发表时间：
2004-08
影响因子：
1.5
通讯作者：
R. Sanders;E. Busser;John P. Moore;Min Lu;B. Berkhout
中科院分区：
文献类型：
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作者：
R. Sanders;E. Busser;John P. Moore;Min Lu;B. Berkhout
HIV-1包膜糖蛋白复合物（Env）可以通过在gp120和gp41亚基之间引入二硫键来稳定。得到的蛋白是单体的，但在gp41的n端七核苷酸重复区保守的Ile559位点上引入一个单螺旋断裂残基可以改善三聚化。为了更深入地了解gp41中的这种替代如何影响Env的结构和功能，我们在病毒复制的背景下评估了对野生型Env的影响。Ile559Gly和Ile559Pro突变对Env的生物合成和Env并入病毒粒子产生不利影响。生物物理学研究表明，Ile559Pro突变基本上破坏了重组gp41外结构域核心折叠成六螺旋束结构。含有Ile559Gly和Ile559Pro替换的病毒复制能力差，但描述了一种恢复复制能力的进化途径。在含有Pro559Leu第一位点假逆转的逃逸病毒中，局部螺旋结构得以恢复，因此Env的生物合成和功能得以恢复。
The HIV-1 envelope glycoprotein complex (Env) can be stabilized by the introduction of a disulfide bond between the gp120 and gp41 subunits. The resulting protein is monomeric, but trimerization can be improved by the introduction of a single helix-breaking residue at the conserved Ile559 site in the N-terminal heptad repeat region of gp41. To provide more insight into how such a substitution in gp41 affects Env structure and function, we evaluated the effect on the wild-type Env in the context of replicating virus. The Ile559Gly and Ile559Pro mutations adversely affect Env biosynthesis and Env incorporation into virions. Biophysical studies show that the Ile559Pro mutation essentially disrupts the folding of a recombinant gp41 ectodomain core into a six-helix bundle structure. Viruses containing the Ile559Gly and Ile559Pro substitutions replicate poorly, but an evolutionary route is described that restores replication competence. In the escape virus, which contains a Pro559Leu first-site pseudoreversion, the local helical structure and, as a consequence, Env biosynthesis and function are restored.