Hanoulle Xavier, Verdegem Dries, Badillo Aurélie, Wieruszeski Jean-Michel, Penin François, Lippens Guy
UGSF, UMR CNRS, IFR, Université des Sciences et Technologies de Lille, Villeneuve d'Ascq, France.
Biochem Biophys Res Commun. 2009 Apr 17;381(4):634-8. doi: 10.1016/j.bbrc.2009.02.108. Epub 2009 Feb 26.
Hepatitis C virus (HCV) non-structural protein 5A (NS5A) is involved both in the viral replication and particle production. Its third domain (NS5A-D3), although not absolutely required for replication, is a key determinant for the production and assembly of novel HCV particles. As a prerequisite to elucidate the precise functions of this domain, we report here the first molecular characterization of purified recombinant HCV NS5A-D3. Sequence analysis indicates that NS5A-D3 is mostly unstructured but that short structural elements may exist at its N-terminus. Gel filtration chromatography, circular dichroism and finally NMR spectroscopy all point out the natively unfolded nature of purified recombinant NS5A-D3. This lack of stable folding is thought to be essential for primary interactions of NS5A-D3 domain with other viral or host proteins, which could stabilize some specific conformations conferring new functional features.
丙型肝炎病毒（HCV）非结构蛋白5A（NS5A）参与病毒复制和病毒颗粒产生过程。其第三个结构域（NS5A-D3）虽然并非复制绝对必需，但却是新型HCV颗粒产生和组装的关键决定因素。作为阐明该结构域精确功能的前提条件，我们在此报告纯化的重组HCV NS5A-D3的首次分子特征分析。序列分析表明，NS5A-D3大多为无结构状态，但在其N端可能存在短结构元件。凝胶过滤色谱、圆二色性以及最终的核磁共振光谱均表明纯化的重组NS5A-D3具有天然未折叠的性质。这种缺乏稳定折叠的状态被认为对于NS5A-D3结构域与其他病毒或宿主蛋白的初级相互作用至关重要，这些相互作用可能会稳定一些赋予新功能特征的特定构象。
