Structural similarity between the p17 matrix protein of HIV-1 and interferon-γ
Structural similarity between the p17 matrix protein of HIV-1 and interferon-γ
复制标题
HIV-1 的 p17 基质蛋白与干扰素-γ 之间的结构相似性
作者：
L. Kay;M. Ikura;A. Bax
人类免疫缺陷病毒（HIV）基质蛋白p17形成病毒核心的外壳，衬在病毒膜的内表面1 -4。蛋白质有几个关键功能。它通过引导gag前体多蛋白p55到宿主细胞膜的靶向信号协调病毒组装1，5-7，并与跨膜蛋白gp 41相互作用，以将env编码的蛋白保留在病毒中8。此外，pi 7含有核定位信号，其将整合前复合物引导至感染细胞的核9。这使得病毒能够感染非分裂细胞，这是HIV和其他慢病毒的显著特征。我们通过核磁共振（NMR）确定了p17的溶液结构，其明确区域的骨架的均方根偏差为0.9 μ m。它由四个由短环连接的螺旋和一个不规则的混合β折叠组成，β折叠提供了一个带正电的表面，用于与膜的内层相互作用。螺旋拓扑结构是不寻常的;布鲁克海文蛋白质数据库只包含一个类似的结构，即免疫调节剂干扰素-γ。
THE human immunodeficiency virus (HIV) matrix protein, p17, forms the outer shell of the core of the virus, lining the inner surface of the viral membrane1–4. The protein has several key functions. It orchestrates viral assembly via targeting signals that direct the gag precursor polyprotein, p55, to the host cell membrane1,5–7 and it interacts with the transmembrane protein, gp41, to retain the env-encoded proteins in the virus8. In addition, pi7 contains a nuclear localization signal that directs the preintegration complex to the nucleus of infected cells9. This permits the virus to infect productively non-dividing cells, a distinguishing feature of HIV and other lentiviruses. We have determined the solution structure of p17 by nuclear magnetic resonance (NMR) with a root-mean square deviation for the backbone of the well-defined regions of 0.9 Å. It consists of four helices connected by short loops and an irregular, mixed β-sheet which provides a positively charged surface for interaction with the inner layer of the membrane. The helical topology is unusual; the Brookhaven protein database contains only one similar structure, that of the immune modulator interferon-γ.