FUNCTIONAL CHARACTERIZATION OF THE POXVIRAL RING PROTEIN

这个子项目是许多研究子项目中的一个 由NIH/NCRR资助的中心赠款提供的资源。子项目和 研究者（PI）可能从另一个NIH来源获得了主要资金， 因此可以在其他CRISP条目中表示。所列机构为 研究中心，而研究中心不一定是研究者所在的机构。 本项目的目的是确定痘病毒毒力因子p28的分子功能。P28被证明是控制巨噬细胞病毒感染的一个重要因素，并且在体外不能感染巨噬细胞与体内感染的自发清除相关。也有一些证据表明，P28保护免受病毒诱导和UV诱导的细胞凋亡。本项目的具体目标1是检验p28保护巨噬细胞免于凋亡的假设。我们最近已经证明，P28是一个环域泛素连接酶，因为P28介导的形成高分子量的泛素化产物的存在下，泛素结合酶，泛素和泛素活化酶E1。此外，我们观察到，泛素是集中在痘病毒工厂中存在的P28表明，P28介导的病毒和/或病毒工厂中的细胞蛋白的泛素化。因此，具体目标2是使用蛋白质组学方法来鉴定直接或间接受P28影响的潜在靶点。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. The goal of this project is to identify the molecular function of the poxviral virulence factor p28. P28 was shown to be an essential factor for controlling viral infection of macrophages and the inability to infect macrophages in vitro correlated with spontaneous clearance of infections in vivo. There is also some evidence that P28 protects against virally induced and UV-induced apoptosis. Specific aim 1 of this project is to test the hypothesis that p28 protects macrophages from apoptosis. We have recently demonstrated that P28 is a RING-domain ubiquitin ligase since P28 mediates the formation of high molecular weight ubiquitinated products in the presence of ubiquitin-conjugating enzymes, ubiquitin and the ubiquitin activating enzyme E1. In addition, we observed that ubiquitin is concentrated in poxvirus factories in the presence of P28 suggesting that P28 mediates the ubiquitination of viral and/or cellular proteins in virus factories. Therefore, Specific aim 2 is to use a proteomics approach to identify potential targets that are directly or indirectly affected by P28.