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 副本整合到宿主 DNA 中。因此，阻止 HIV DNA 整合的治疗策略对于阻止 HIV 感染至关重要。细胞因子在此病毒过程中的作用尚不清楚。晶状体上皮衍生生长因子 p75 (LEDGF/p75) 是一种经过充分表征的 HIV DNA 整合细胞辅助因子。然而，慢病毒为何进化出对这种细胞蛋白的依赖以实现有效的病毒 DNA 整合仍不清楚。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结合在一起。然而，这种机制并不能解释染色质结合的HIV预整合复合物使用的策略来获得宿主DNA，这是整合到宿主DNA的必要步骤，或者进一步利用细胞DNA修复机制来促进后整合。 -整合DNA修复。我实验室的新发现为 HIV 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 LEDGF/p75 中存在几个蛋白质基序，这些基序对于 HIV DNA 以不依赖染色质束缚的方式整合是必需的。这些基序包含磷酸化或SUMO化的残基，或者预计是蛋白质-蛋白质相互作用模块的一部分的残基。我们假设这些 LEDGF/p75 基序参与招募与 HIV DNA 整合过程有关的细胞蛋白。为了进一步支持该模型，我们的实验室已经鉴定出新型 LEDGF/p75 相互作用蛋白，这些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 依赖性以实现最佳的 HIV DNA 整合，因为这种细胞蛋白：（i）将 HIV 预整合复合物束缚到参与主动转录的染色质子区域，并且（ii）提供病毒通过 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，尤其是在主动转录 DNA 时非常活跃。此外，我们假设一些 LEDGF/p75 相互作用蛋白会损害该蛋白的 HIV 辅因子活性。在本提案中，我们将展示这种新颖模型的基本方面。具体来说，我们将： (i) 定义与 DNA 修复和染色质重塑有关的 LEDGF/p75 相互作用蛋白在 HIV DNA 整合中的作用。 (ii) 确定涉及翻译后修饰和蛋白质-蛋白质相互作用的 LEDGF/p75 基序的 HIV DNA 整合的功能含义。 (iii) 通过确定全基因组范围内 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支持。