Structural Biophysics of HIV Alternative Splicing

HIV选择性剪接的结构生物物理学

• 批准号: 8666106
• 负责人: Blanton Smith Tolbert
• 金额: $ 0.39万
• 依托单位: CASE WESTERN RESERVE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-08-01 至 2017-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8666106
• 关键词: 3' Splice Site; Acquired Immunodeficiency Syndrome; Adopted; Affect; Affinity; Alternative Splicing; Binding; Binding Sites; Biochemical; Biological Assay; Biophysics; Calorimetry; Complex; DNA Sequence Rearrangement; Elements; Ensure; Environment; Event; Exons; Genome; Goals; HIV; HIV Genome; Health; Higher Order Chromatin Structure; Homeostasis; In Vitro; Integration Host Factors; Intervention; Knowledge; Lead; Light; Maps; Messenger RNA; Methods; Modeling; Molecular; Monitor; N-terminal; NMR Spectroscopy; Pathway interactions; Pattern; Property; RNA; RNA Sequences; RNA Splicing; Recruitment Activity; Regulation; Regulatory Element; Repression; Research; Resolution; Site; Site-Directed Mutagenesis; Structure; Therapeutic Intervention; Thermodynamics; Titrations; Transcript; Viral; Virus; Work; acrosome stabilizing factor; base; biochemical model; hnRNP A1; in vivo; innovation; insight; new therapeutic target; novel; novel strategies; research study; stem; three dimensional structure; viral RNA

DESCRIPTION (provided by applicant): The long-term objective of this proposal is to develop an innovative structural, biophysical, and functional biochemical framework to advance our understanding of HIV splicing mechanisms. The HIV genome is synthesized as a single polycistronic RNA transcript that undergoes regulated splicing to ensure mRNA homeostasis. Aberrations in the viral splicing machinery impair HIV replication fidelity and in some cases render the virus less infectious. Thus, HIV splicing pathways represent novel targets for therapeutic intervention. Splicing decisions are determined by the dynamic assembly/disassembly of trans host factors with cis viral RNA control elements; however, the underlying molecular events that determine whether a splice site will be activated or repressed remain elusive. Knowledge of the physical and functional determinants of how one highly conserved splice site gets differentially regulated by two trans host factors offers the opportunit to define a mechanism. Hence, the immediate goal of this proposal is to identify the molecular principles that HIV uses to co-opt the mutually antagonistic factors, hnRNP A1 (A1) and ASF, in order to regulate its 3' splice site A7 (ssA7). Furthermore, A1 and ASF regulate other conserved HIV splice sites via poorly characterized mechanisms; thus, the work proposed here is likely to have broad implications on our understanding of HIV splicing in general and may lead to new approaches to thwart HIV replication. The specific aims of this project are to: (1) Determine the contribution of structure to target site selection by A1 and ASF, (2) Elucidate the bio-thermodynamic underpinnings of mutual antagonism between A1 and ASF, and (3) Investigate the molecular origins of cooperativity in ssA7 regulation.

描述（由申请人提供）：该提案的长期目标是开发一种创新的结构、生物物理和功能生化框架，以增进我们对 HIV 剪接机制的理解。 HIV 基因组被合成为单个多顺反子 RNA 转录本，经过受调控的剪接以确保 mRNA 稳态。病毒剪接机制的异常会损害HIV复制的保真度，并且在某些情况下会降低病毒的传染性。因此，HIV 剪接途径代表了治疗干预的新靶点。剪接决策由反式宿主因子与顺式病毒RNA控制元件的动态组装/分解决定；然而，决定剪接位点是否被激活或抑制的潜在分子事件仍然难以捉摸。了解一个高度保守的剪接位点如何受到两个反式宿主因子差异调节的物理和功能决定因素，为定义一种机制提供了机会。因此，该提案的直接目标是确定 HIV 用于选择相互拮抗因子 hnRNP A1 (A1) 和 ASF 的分子原理，以调节其 3' 剪接位点 A7 (ssA7)。此外，A1 和 ASF 通过尚未充分表征的机制来调节其他保守的 HIV 剪接位点。因此，这里提出的工作可能会对我们对艾滋病毒剪接的总体理解产生广泛的影响，并可能带来阻止艾滋病毒复制的新方法。该项目的具体目标是：（1）确定结构对 A1 和 ASF 靶位选择的贡献，（2）阐明 A1 和 ASF 之间相互拮抗的生物热力学基础，以及（3）研究 ssA7 调节中协同性的分子起源。