Understanding the fundamental mechanisms of viral activation in the host

尽管多年来对流感病毒进行了大量的研究，但对于流感融合蛋白血凝素是如何被宿主酶处理而变得具有传染性的，人们知之甚少。此外，直到最近才发现了一些宿主流感激活酶。我们已经在人类呼吸道的细胞中发现了一种这样的酶。到目前为止，关于宿主酶激活流感血凝素的现行教条是，存在于裂解位点的氨基酸序列决定了将进行融合蛋白激活的酶的类型。基于文献和我们最近的发现，我们认为这种关于血凝素活化的观点过于简单，并且存在病毒血凝素和宿主酶相互作用的其他关键决定因素，这些决定因素导致蛋白质的加工和活化。在这个建议中，我们的目标是阐明控制这种相互作用过程的力量和流感血凝素的结构特征，这些特征影响和对相互作用的发生至关重要。为此，我们将使用尖端的生化、生物物理和分子技术来研究H1和H3亚型病毒与宿主的两种流感激活酶的相互作用，其中一种是几年前发现的，另一种是我们最近新发现的。因此，本研究计划的长期目标是了解病毒融合蛋白与宿主酶相互作用的基本力量、结构决定因素和机制，从而导致它们的激活。通过提供病毒蛋白如何与宿主中激活它们的酶相互作用的基本信息，该研究项目将对病毒学领域产生重大影响。它还应该为学术环境和生物技术/制药部门对开发新型流感抗病毒药物感兴趣的研究人员提供重要信息。加拿大人将通过创造新的加拿大知识产权在经济上受益于这项研究，并通过未来开发新的抗病毒疗法在公共卫生方面受益于这项研究。

Although much research has been done on the influenza virus over the years, strikingly very little is known about the way the influenza fusion protein hemagglutinin is processed by host enzymes for it to become infectious. Furthermore, only recently have some of the host influenza activating enzymes been identified. We have identified one such enzyme in the cells lining the respiratory tract of humans. To date the current dogma on influenza hemagglutinin activation by host enzymes is that the amino acid sequence present at the cleavage site dictates the type of enzyme that will carry out the activation of the fusion protein. Based on the literature and on our most recent discoveries, we believe that this view of hemagglutinin activation is overly simplistic and that there exist other crucial determinants of viral hemagglutinin and host enzyme interaction, which lead to the protein's processing and activation. In this proposal we aim to elucidate the forces that govern this interaction process and the structural features of influenza hemagglutinin that influence and that are critical for the interaction to take place. To do so, we will use sophisticated and cutting-edge biochemical, biophysical and molecular techniques to study the interaction of H1 and H3 subtype viruses with two influenza-activating enzymes of the host, one that has been identified a few years ago and one that we have newly identified recently. Thus the long-term goal of this research program is to understand the fundamental forces, structural determinants and mechanisms of the interaction of viral fusion proteins with host enzymes, which lead to their activation. This research program should have a significant impact on the field of virology by providing fundamental information on how viral proteins interact with enzymes that activate them in the host. It should also provide vital information to researchers in both academic settings and in the biotech/pharmaceutical sectors who are interested in developing novel influenza antivirals. Canadians will benefit from this research economically through the generation of novel Canadian intellectual property, and in public health through the future development of new antiviral therapies.