HARC Center: HIV Accessory and Regulatory Complexes

HARC 中心：HIV 辅助和调节复合物

• 批准号: 8410292
• 负责人: ALAN D FRANKEL
• 金额: $ 415.4万
• 依托单位: UNIVERSITY OF CALIFORNIA, SAN FRANCISCO
• 依托单位国家: 美国
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-08-27 至 2017-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8410292
• 关键词: HARC; Center; HIV; Accessory; Regulatory

DESCRIPTION (provided by applicant): HIV requires the host cell machinery for replication. Many complexes hijacked by HIV have been identified, but structures are known in only a few cases. The HARC Center is taking a broad systems-to-structure approach to this problem, having identified and validated new host complexes through a comprehensive proteomics effort. Primary biological aims of the Center are to achieve comprehensive structural pictures of: (1) how the accessory proteins Vif, Vpu, Vpr, and the viral protease PR disarm host defenses and circumvent viral restriction via degradation pathways, and (2) how the regulatory proteins Tat and Rev hijack the host transcription and RNA trafficking machinery to express and package viral RNAs. There is growing evidence that HIV accessory proteins primarily target host antiviral restriction factors for destruction. For Vif, we will determine the structures of the E3 ligase complex and interactions with APOBEC, and evaluate the functional roles of the CBF? cofactor and post-translational modifications (PTMs). For Vpu, we will determine the structures of restriction factor complexes and map effects of Vpu on ubiquitination. For Vpr, we will validate new host interactions and mechanisms and assemble complexes for structure determination. For PR, we will determine the structures and functions of new host target complexes and measure the levels of PR activity during infection. The regulatory proteins Tat and Rev hijack host transcription and RNA export machineries. For Tat, we will determine the structures of newly discovered AFF4 elongation complexes, and characterize other host factors, PTMs, and inhibitory 7SK snRNP complexes. For Rev, we will determines the structures of Rev-RRE nuclear export complexes, map viral RNA structures, and characterize the roles of new host proteins in post export functions. The HARC Center also relies on technology innovation from four cores. The EM Core will develop methods to determine structures of membrane protein complexes, and use Fabs to solve the structures of small HIV-host complexes. The Proteomics Core will extend mass spectrometry analyses to host protein complexes and map HIV-dependent host PTMs. The Computational Core will develop methods to characterize allostery and detailed models to study PTMs. The Virology Core will measure effects of new host interactions on HIV replication and coupled activities of Tat and Rev. The individual projects and technologies depend critically on an extensive network of collaborators, which will be expanded through a Collaborative Opportunity Fund. PUBLIC HEALTH RELEVANCE: Existing anti-HIV therapeutics have extended the life expectancy of infected individuals, however major limitations remain, including drug resistance. By determining structures of key HIV accessory and regulatory complexes, we will achieve a more complete molecular understanding of how the virus hijacks the host cell machinery, and also identify new targets for therapeutic intervention in the continuing battle against AIDS.

描述（由申请人提供）：HIV需要宿主细胞机制进行复制。许多被艾滋病毒劫持的复合物已经被鉴定出来，但只有少数情况下的结构是已知的。HARC中心正在采取一种广泛的系统到结构的方法来解决这个问题，通过全面的蛋白质组学工作确定并验证了新的宿主复合物。该中心的主要生物学目标是获得全面的结构图：（1）辅助蛋白Vif，Vpu，Vpr和病毒蛋白酶PR如何解除宿主防御并通过降解途径规避病毒限制，以及（2）调节蛋白达特和Rev如何劫持宿主转录和RNA运输机制以表达和包装病毒RNA。越来越多的证据表明，HIV辅助蛋白主要针对宿主的抗病毒限制因子进行破坏。对于Vif，我们将确定E3连接酶复合物的结构和与APOBEC的相互作用，并评估CBF的功能作用？辅因子和翻译后修饰（PTM）。对于Vpu，我们将确定限制性因子复合物的结构，并绘制Vpu对泛素化的影响。对于Vpr，我们将验证新的宿主相互作用和机制，并组装复合物进行结构测定。对于PR，我们将确定新的宿主靶复合物的结构和功能，并测量感染期间PR活性的水平。调节蛋白达特和Rev劫持宿主转录和RNA输出机制。对于达特，我们将确定新发现的AFF 4延伸复合物的结构，并表征其他宿主因子、PTM和抑制性7SK snRNP复合物。对于Rev，我们将确定Rev-RRE核输出复合物的结构，绘制病毒RNA结构，并表征新宿主蛋白在输出后功能中的作用。HARC中心还依赖于四个核心的技术创新。EM Core将开发确定膜蛋白复合物结构的方法，并使用Fab来解决小型HIV-宿主复合物的结构。蛋白质组学核心将把质谱分析扩展到宿主蛋白质复合物，并绘制依赖艾滋病毒的宿主PTM。计算核心将开发表征变构的方法和研究PTM的详细模型。病毒学核心将衡量艾滋病毒复制和耦合活动的达特和Rev的新主机的相互作用的影响。个别项目和技术严重依赖于广泛的合作者网络，这将通过合作机会基金扩大。 公共卫生相关性：现有的抗艾滋病毒疗法延长了受感染个体的预期寿命，但仍然存在重大限制，包括耐药性。通过确定关键的HIV辅助和调节复合物的结构，我们将实现对病毒如何劫持宿主细胞机制的更完整的分子理解，并确定在持续对抗艾滋病的治疗干预的新靶点。