Structural Studies of Virus and Receptor Interaction

描述(申请人提供)：项目概要：在我目前的博士后职位上推进工作是本申请中描述为两个具体目标的更直接的目标。相对于第一个目标，不同密切相关的病毒已经适应以各种方式结合相同的宿主蛋白，这表明一种趋同的进化为病毒提供了优势。结合这种蛋白的病毒适应也会改变致病性。使用结构方法来绘制病毒表面相互作用的区域可能会提供对受体使用的致病后果的见解，并补充现有的突变研究。第二个目标是了解细小病毒对宿主蛋白的不对称使用。在体外，只有一个可溶性受体分子与之结合是意想不到的，也是令人兴奋的。结合受体可能会引起病毒的构象变化，并形成对继续感染至关重要的不对称特征，可能会导致基因组的脱落。或者，这种小的二十面体病毒可能并不像之前的结构研究所表明的那样完全对称。在结构测定中广泛使用的平均技术可能最终隐藏了这种病毒和其他病毒系统中功能不对称特征的存在。其目的是调查这两种可能性。在我的博士工作中对病毒组装的研究使我获得了博士后学位，在那里我同时学习了低温EM重建技术和X射线结晶学。本申请中概述的项目将使用这两种技术，并提供机会更深入地研究重建程序套件、过去的理论知识以及如何使用特定程序。要真正创造性地解决问题，需要对特定的算法和例程进行全面的计算理解，以便根据手头的数据量身定做重建过程，并获得最高质量的结果。这一过渡期将使我能够继续在学术环境中继续进行病毒结构的独立研究的最终目标，为该领域做出有价值的贡献，并提供机会来传递灌输给我的技能和对科学的热情。相关性：微小核糖核酸病毒会引起严重的心肌炎、无菌性脑膜炎，并与糖尿病有关。本研究将探讨受体结合在致病性中的作用。细小病毒中受体的使用可能导致功能上必要的偏离确切的二十面体对称性。更好地了解这一现象可能会为抗病毒药物提供准确的靶点，并在其他系统中有更广泛的应用。此外，特别是对犬细小病毒的研究可能有助于澄清物种跳跃。

DESCRIPTION (provided by applicant): Project Summary: Advancing the work from my current post doctoral position is the more immediate goal described in this application as two specific aims. Relative to the first aim, different closely related viruses have adapted to bind the same host protein in a variety of ways, suggesting a convergent evolution that offers an advantage to the virus. The viral adaptation to bind this protein also alters pathogenicity. Using a structural approach to map the area of interaction on the surface of the virus may provide insights into the pathogenic consequences of receptor usage, and complement the existing mutational studies. The second aim is directed at understanding the asymmetric use of a host protein by a parvovirus. The binding of only one soluble receptor molecule in vitro was unexpected and exciting. Possibly, binding receptor instigates a conformational change to the virus and formation of an asymmetric feature critical to continue infection, perhaps leading to the uncoating of the genome. Alternatively, the small icosahedral virus may not be as perfectly symmetrical as structural studies have previously suggested. Averaging techniques used widely in structural determinations may have ultimately hidden from view the presence of functional asymmetric features in this virus and other viral systems. The aim is to investigate both possibilities. The study of viral assembly in my doctoral work, led to a post doc where I have learned both cryoEM reconstruction techniques and X-ray crystallography. The projects outlined in this application will use both techniques and provide the opportunity to delve deeper into the program suites for reconstruction, past knowledge of theory and merely how to use particular programs. To be truly creative in problem solving requires a comprehensive computational understanding of the specific algorithms and routines in order to tailor a reconstruction process to the data at hand and achieve the highest quality results. This transition period will allow me to proceed toward the ultimate goal of continuing independent research in viral structure in an academic setting, making worthy contributions to the field, and providing the opportunity to pass on the skills and the enthusiasm for science that have been instilled in me. Relevance: Picornaviruses cause severe myocarditis, aseptic meningitis and are implicated in diabetes. This study will investigate the contribution of receptor binding to pathogenicity. Receptor usage in parvoviruses may lead to functionally necessary deviations from exact icosahedral symmetry. A better understanding of this phenomenon may provide an exact target for antivirals and have broader application in other systems. Furthermore, study of canine parvovirus in particular may lead to clarification of species jumping.