Molecular basis of protein-ligand interactions.

这项研究计划的长期目标是了解蛋白质-配体相互作用的分子机制和功能后果。我们对与金属离子和/或其他蛋白质相互作用的蛋白质特别感兴趣，因为在我们对蛋白质如何识别这些配体的理解上仍然存在重要的差距。病毒蛋白特别适合于这些研究，因为一种蛋白质经常具有许多不同的酶活性，因此可以与不同的配体相互作用。在目前的研究计划中，我们将重点放在丙型肝炎病毒(HCV)的NS5A蛋白上。我们认为，了解NS5A的功能可以提高对丙型肝炎病毒感染和病毒传播的认识。 细胞中存在各种各样的金属离子。对于大多数蛋白质来说，金属离子的存在对活性/功能至关重要。在NS5A蛋白的晶体结构中发现了一个锌原子，它似乎对蛋白质的功能和病毒复制都至关重要。然而，这个锌原子在蛋白质中的确切作用仍然是未知的，它的功能作用还没有得到满意的解释，仍然是一个争论和猜测的问题。虽然NS5A的酶功能尚不清楚，但它是丙型肝炎病毒复制酶复合体的重要组成部分，在细胞途径和过程中发挥着广泛的作用，包括先天性免疫、宿主细胞的生长和增殖。NS5A最令人兴奋的研究领域之一是它与宿主细胞蛋白的相互作用以及它调节宿主途径的能力。幸运的是，已经确定了各种细胞结合伙伴。我们相信，更好地了解NS5A和细胞蛋白之间的相互作用将揭示病毒诱导的细胞通路调节的关键特征。 我们这项研究计划的长期目标是了解决定酶及其配体之间相互作用的分子决定因素，并了解它们的功能后果。为实现这些目标，我们目前的具体目标是： 1.研究金属离子与丙型肝炎病毒NS5A蛋白结合的热力学和结构影响； 2.研究细胞蛋白与NS5A蛋白之间的相互作用及其功能后果。 3.研究NS5A对细胞基因表达的调控作用。 研究生和本科生都将是我们研究计划的推动力。通过他们在分子生物学、生物化学和结构生物学领域的培训，他们将继续为该领域做出原创贡献。显然，这是我们的优先事项，使用NSERC的拨款，为有兴趣奖励研究职业的学生提供出色的培训。

The long-term objective of this research program is to understand the molecular mechanisms and functional consequences of proteins-ligand interactions. We are especially interested in proteins that interact with metal ions and/or other proteins because there are still important gaps in our understanding of how proteins recognize these ligands. Viral proteins are especially well suited for these studies because a single protein frequently harbors many different enzymatic activities and can therefore interact with various ligands. In the current research program, we are focusing on the NS5A protein from the Hepatitis C virus (HCV). We believe that understanding the functions of NS5A could lead to an improved knowledge of HCV infection and viral propagation. A wide variety of metal ions are found in cells. For most proteins, the presence of metal ions is crucial for activity/function. A zinc atom is found in the crystal structure of the NS5A protein and appears critical for both the function of the protein and for viral replication. However, the precise role of this zinc atom in the protein is still unknown and its functional role has not yet received a satisfactory explanation and is still a matter of debate and speculation. While no known enzymatic function has been ascribed to NS5A, it is an essential component of the HCV replicase complex and exerts a wide range of effects on cellular pathways and processes, including innate immunity, host cell growth and proliferation. One of the most exciting areas of research on NS5A is its interactions with host cell proteins and its ability to modulate host pathways. Fortunately, various cellular binding partners have already been identified. We believe that a better understanding of the interactions between NS5A and cellular proteins will reveal key features in the virus-induced modulation of cellular pathways. Our long-term objective for this research program is to understand the molecular determinants that dictate the interactions between enzymes and their ligands, and to understand their functional consequences. To achieve these goals, our current specific objectives are: 1. To characterize the thermodynamic and structural consequences of metal ion binding to the HCV NS5A protein; 2. To characterize the interaction between cellular proteins and the NS5A protein, and their functional consequences. 3. To investigate the ability of NS5A to modulate the expression of cellular genes. Both graduate and undergraduate students will be the driving force in our research program. Through their training in the fields of molecular biology, biochemistry, and structural biology they will continue to make original contributions to the field. Clearly, it is a priority for us to use the NSERC grant to provide excellent training for students interested in rewarding careers in research.