Mechanisms of Enterovirus Entry

利用高分辨率冷冻电镜（cryo EM）研究柯萨奇病毒B3 （CVB3）通过柯萨奇病毒和腺病毒受体（CAR）进入宿主细胞的机制。CVB3是一种人类病原体，可引起心肌炎、胰腺炎，最近与青少年糖尿病的发病有关。我们建议的CVB3进入研究是对先前有效批准期的延续。之前的部分工作是与费城儿童医院传染病科的杰弗里·伯格尔森博士合作完成的，他已经退休了。继续研究肠道病毒进入的拟议项目包括与FDA的Konstantin Chumakov合作。Chumakov将与我们一起探索上一个资助期最有希望的结果之一，即发现CAR足迹中CVB3衣壳上的一个区域在其他三种病毒及其受体中是保守的，因此使用三种不同的宿主蛋白进入四个物种。进一步检查显示1)该区域在所有人类肠道病毒中高度保守，包括所有三株脊髓灰质炎病毒。2)共有4个不同的高度保守区域。先前的工作和我们的初步结果将这些保守位点与入口相关的功能联系起来。我们的结构/功能研究将包括测试每个区域的功能和作为迫切需要的抗病毒药物的靶点。我们将使用传统的二十面体平均方法和不对称重建方法，其中一些是我们最近开发的。

Using high resolution cryo electron microscopy (Cryo EM) we will investigate the mechanisms used by coxsackievirus B3 (CVB3) to enter host cells by engaging the coxsackievirus and adenovirus receptor (CAR). CVB3 is a human pathogen that causes myocarditis, pancreatitis, and has recently been linked to the onset of juvenile diabetes mellitus. Our proposed studies of CVB3 entry are a continuation of a productive previous granting period. Part of the previous work done was in collaboration with Dr. Jeffery Bergelson, Division of Infectious Diseases at Children's Hospital at Philadelphia, who has since retired. The proposed projects to continue studies of enterovirus entry include a collaboration with Konstantin Chumakov, FDA. Chumakov will work with us to explore one of the most promising results from the previous funding period, which was the discovery that a region in the CAR footprint onto the CVB3 capsid is conserved among three other viruses and their receptors, thus crossing four species using three different host proteins for entry. Further examination showed 1) the region is highly conserved among all human enteroviruses, including all three strains of poliovirus. 2) there are in total four different highly conserved regions. Previous work and our preliminary results link these conserved sites to functions linked to entry. Our structure/function studies will include testing each region for function and as targets for antivirals that are desperately needed. We will use both traditional icosahedrally averaged approaches along with asymmetric reconstruction approaches, some of which have been recently developed by us.