法国国家科研中心2日发表公报说,该机构与巴斯德研究所合作,通过揭示基孔肯雅病毒表面蛋白质的3D结构,掌握了这种病毒侵入细胞的机制,这一发现将有助于开发新的抗病毒药物。
公报称,研究人员借助电子显微镜清楚观测到这种病毒表面蛋白质的3D结构,他们发现,蛋白质E1、E2、p62等在病毒入侵机制中发挥着关键作用。首先,基孔肯雅病毒会在E2的帮助下附着在细胞膜上,然后被运送到核内体,后者的酸性环境会激发E1的活性,在它的作用下,病毒与核内体融为一体,并趁机在细胞中释放核糖核酸,从而复制更多的病毒。在完成对一个细胞的感染后,病毒表面的蛋白质会重新组合,在p62的帮助下冲破酸性环境,寻找新的传播目标。
基孔肯雅病毒是导致基孔肯雅热的元凶。基孔肯雅热是以发热、皮疹及关节痛为主要特征的急性传染病,主要在南亚、非洲中部和东部等地区传播,目前尚无防治的特效药或疫苗。研究人员说,掌握基孔肯雅病毒的传播机制将有助于提高基孔肯雅热的防治水平。(生物谷Bioon.com)
生物谷推荐原文出处:
Nature doi:10.1038/nature09555
Glycoprotein organization of Chikungunya virus particles revealed by X-ray crystallography
James E. Voss,Marie-Christine Vaney,Stéphane Duquerroy,Clemens Vonrhein,Christine Girard-Blanc,Elodie Crublet,Andrew Thompson,Gérard Bricogne& Félix A. Rey
Chikungunya virus (CHIKV) is an emerging mosquito-borne alphavirus that has caused widespread outbreaks of debilitating human disease in the past five years1. CHIKV invasion of susceptible cells is mediated by two viral glycoproteins, E1 and E2, which carry the main antigenic determinants and form an icosahedral shell at the virion surface. Glycoprotein E2, derived from furin cleavage of the p62 precursor into E3 and E2, is responsible for receptor binding, and E1 for membrane fusion. In the context of a concerted multidisciplinary effort to understand the biology of CHIKV2, here we report the crystal structures of the precursor p62–E1 heterodimer and of the mature E3–E2–E1 glycoprotein complexes. The resulting atomic models allow the synthesis of a wealth of genetic, biochemical, immunological and electron microscopy data accumulated over the years on alphaviruses in general. This combination yields a detailed picture of the functional architecture of the 25?MDa alphavirus surface glycoprotein shell. Together with the accompanying report on the structure of the Sindbis virus E2–E1 heterodimer at acidic pH (ref. 3), this work also provides new insight into the acid-triggered conformational change on the virus particle and its inbuilt inhibition mechanism in the immature complex.