Regulation of the HIV cofactor activity of LEDGF/p75 by interacting proteins

通过相互作用蛋白调节 LEDGF/p75 的 HIV 辅因子活性

• 批准号: 8479118
• 负责人: Manuel Llano
• 金额: $ 34.81万
• 依托单位: UNIVERSITY OF TEXAS EL PASO
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-07-05 至 2015-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8479118
• 关键词: Accounting; Acquired Immunodeficiency Syndrome; Amino Acid Motifs; Anti-Retroviral Agents; Binding; Binding Proteins; Cell physiology; Cells; Chromatin; Collaborations; Communicable Diseases; Complex; DNA; DNA Integration; DNA Repair; DNA-Directed RNA Polymerase; Dependency; Failure; Genetic; Genetic Transcription; Genome; Goals; HIV; Human Genome; Infection; Integrase; Laboratories; Life Cycle Stages; Location; Modeling; Molecular; Mutation; Pharmaceutical Preparations; Phosphorylation; Poly(ADP-ribose) Polymerases; Positioning Attribute; Post-Translational Protein Processing; Predisposition; Process; Proteins; Proviruses; Public Health; Recruitment Activity; Regulation; Reporting; Research; Research Proposals; Role; Site; Structure; Subfamily lentivirinae; Therapeutic; Time; Viral; Viral Genome; Virus; Virus Diseases; Virus Integration; Work; chromatin immunoprecipitation; chromatin remodeling; cofactor; drug resistant virus; experience; genome-wide; lens epithelium-derived growth factor; mutant; new therapeutic target; novel; pandemic disease; prevent; protein protein interaction; protein transport; therapeutic target; tool; trafficking; transcriptional coactivator p75; viral DNA

DESCRIPTION (provided by applicant): HIV infection requires the integration of a DNA copy of the viral genome into the host DNA. Therefore therapeutic strategies to prevent HIV DNA integration are essential to block HIV infection. The role of cellular factors in this viral process is poorly defined. The Lens Epithelium-Derived Growth Factor p75 (LEDGF/p75) is a well characterized cellular cofactor of HIV DNA integration. However, it remains unexplained why Lentiviruses have evolved dependency of this cellular protein for efficient viral DNA integration. Work from my group and others have determined that LEDGF/p75 tethers the HIV integration complex to the host chromatin. However, this mechanism does not explain the strategies used by the chromatin-bound HIV pre-integration complex to gain access to the host DNA, a necessary step for integration to the host DNA, or to exploit further the cellular DNA repair machinery to promote post-integration DNA repair. New findings from my laboratory provide potential molecular explanations for these essential aspects of the HIV DNA integration process. We have demonstrated for the first time the existence of several protein motifs in LEDGF/p75 necessary for the HIV DNA integration in a chromatin tethering-independent manner. These motifs contain residues that are phosphorylated or SUMOylated, or that are predicted to be part of protein-protein interaction modules. We have postulated that these LEDGF/p75 motifs are involved in recruiting cellular proteins implicated in the HIV DNA integration process. In further support of this model, our laboratory has identified novel LEDGF/p75- interacting proteins known to be involved in chromatin remodeling, DNA repair, and transcriptional elongation. In summary, our model postulate that Lentiviruses have evolved LEDGF/p75-dependency for optimal HIV DNA integration because this cellular protein: (i) tethers the HIV pre-integration complex to subregions of the chromatin engaged in active transcription, and (ii) provides to the virus, through LEDGF/p75-specific protein- protein interactions, access to the host DNA and to DNA repair mechanisms particularly active in actively transcribe DNA. In addition, we postulate that some LEDGF/p75-interacting proteins will impair the HIV cofactor activity of this protein. In this proposal we will demonstrate essential aspects of this novel model. Specifically we will: (i) Define the role in HIV DNA integration of LEDGF/p75-interacting proteins implicated in DNA repair and chromatin remodeling. (ii) Determine the functional implications in HIV DNA integration of LEDGF/p75 motifs involved in post-translational modifications and protein-protein interactions. (iii) Provide further support to our model by determining genome-wide the correlation between LEDGF/p75 location and HIV DNA integration site selection.

描述（由申请人提供）：HIV感染需要将病毒基因组的DNA拷贝整合到宿主DNA中。因此，预防HIV DNA整合的治疗策略对于阻断HIV感染至关重要。细胞因子在这一病毒过程中的作用尚不清楚。透镜上皮衍生生长因子p75（LEDGF/p75）是HIV DNA整合的一种充分表征的细胞辅因子。然而，仍然无法解释为什么慢病毒已经进化出对这种细胞蛋白的依赖性以进行有效的病毒DNA整合。我的团队和其他人的工作已经确定LEDGF/p75将HIV整合复合物与宿主染色质联系在一起。然而，这一机制并不能解释染色质结合的HIV整合前复合物进入宿主DNA（整合到宿主DNA的必要步骤）或进一步利用细胞DNA修复机制促进整合后DNA修复所使用的策略。我实验室的新发现为艾滋病毒DNA整合过程的这些重要方面提供了潜在的分子解释。我们首次证明了LEDGF/p75中存在几种蛋白质基序，这些基序是HIV DNA以染色质束缚独立的方式整合所必需的。这些基序含有磷酸化或SUMO化的残基，或预测为蛋白质-蛋白质相互作用模块的一部分。我们推测这些LEDGF/p75基序参与招募HIV DNA整合过程中涉及的细胞蛋白。为了进一步支持这一模型，我们的实验室已经确定了新的LEDGF/p75相互作用蛋白，已知参与染色质重塑，DNA修复和转录延伸。总之，我们的模型假设慢病毒已经进化出LEDGF/p75依赖性以实现最佳HIV DNA整合，因为这种细胞蛋白：（i）将HIV整合前复合物束缚到参与主动转录的染色质亚区，和（ii）通过LEDGF/p75特异性蛋白质-蛋白质相互作用，接触宿主DNA和DNA修复机制，在主动转录DNA中特别活跃。此外，我们假设，一些LEDGF/p75相互作用的蛋白质将损害HIV辅因子的活性，这种蛋白质。在本提案中，我们将展示这种新模式的基本方面。具体来说，我们将：（i）定义LEDGF/p75相互作用蛋白在HIV DNA整合中的作用，这些蛋白参与DNA修复和染色质重塑。(ii)确定LEDGF/p75基序参与翻译后修饰和蛋白质-蛋白质相互作用在HIV DNA整合中的功能意义。(iii)通过确定全基因组LEDGF/p75位置与HIV DNA整合位点选择之间的相关性，为我们的模型提供进一步的支持。