Transient Structure and SH3 Interaction Sites in an Intrinsically Disordered Fragment of the Hepatitis C Virus Protein NS5A
Transient Structure and SH3 Interaction Sites in an Intrinsically Disordered Fragment of the Hepatitis C Virus Protein NS5A
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DOI：
10.1016/j.jmb.2012.04.023
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发表时间：
2012-07-20
影响因子：
5.6
通讯作者：
Brutscher, Bernhard
中科院分区：
文献类型：
--
作者：
Feuerstein, Sophie;Solyom, Zsofia;Brutscher, Bernhard
了解病毒复制和颗粒组装的分子机制具有重要的基础和生物医学意义。内在构象紊乱在病毒蛋白及其通过瞬时填充结构元件与其他病毒和宿主细胞蛋白的相互作用中起着重要作用。本文报道了丙型肝炎病毒非结构蛋白5A （NS5A）固有无序188-残基片段的研究结果，该片段包含一个经典的聚脯氨酸Src同源性3 （SH3）结合基序，采用灵敏度和分辨率优化的多维核磁共振方法，并结合小角度x射线散射数据。我们的研究提供了该NS5A片段的瞬态局部和远程结构的详细原子分辨率信息，以及快速时间尺度动力学。此外，我们可以表征两种不同的相互作用模式与Bin1（桥接整合蛋白1）的SH3结构域，一个促凋亡的肿瘤抑制因子。尽管该蛋白在很大程度上是无序的，但它包含三个区域，这些区域暂时采用a-螺旋结构，部分由远程三级相互作用稳定。其中两个瞬时a-螺旋形成非规范SH3结合基序，允许低亲和SH3结合。我们的结果有助于更好地理解NS5A蛋白在丙型肝炎病毒感染中的作用。目前的工作还强调了核磁共振光谱表征多种结合事件的能力，包括球状和高度无序蛋白质之间的短暂瞬态相互作用。(C) 2012 Elsevier Ltd.版权所有。
Understanding the molecular mechanisms involved in virus replication and particle assembly is of primary fundamental and biomedical importance. Intrinsic conformational disorder plays a prominent role in viral proteins and their interaction with other viral and host cell proteins via transiently populated structural elements. Here, we report on the results of an investigation of an intrinsically disordered 188-residue fragment of the hepatitis C virus non-structural protein 5A (NS5A), which contains a classical poly-proline Src homology 3 (SH3) binding motif, using sensitivity- and resolution-optimized multidimensional NMR methods, complemented by small-angle X-ray scattering data. Our study provides detailed atomic-resolution information on transient local and long-range structure, as well as fast time scale dynamics in this NS5A fragment. In addition, we could characterize two distinct interaction modes with the SH3 domain of Bin1 (bridging integrator protein 1), a pro-apoptotic tumor suppressor. Despite being largely disordered, the protein contains three regions that transiently adopt a-helical structures, partly stabilized by long-range tertiary interactions. Two of these transient a-helices form a noncanonical SH3-binding motif, which allows low-affinity SH3 binding. Our results contribute to a better understanding of the role of the NS5A protein during hepatitis C virus infection. The present work also highlights the power of NMR spectroscopy to characterize multiple binding events including short-lived transient interactions between globular and highly disordered proteins. (C) 2012 Elsevier Ltd. All rights reserved.