Molecular mech/gene expression reprogramming by HIV TAT

HIV TAT 的分子机械/基因表达重编程

• 批准号: 6985350
• 负责人: ANNA ALDOVINI
• 金额: $ 41.26万
• 依托单位: BOSTON CHILDREN'S HOSPITAL
• 依托单位国家: 美国
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-12-01 至 2009-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6985350
• 关键词: Adenoviridae; DNA binding protein; HIV infections; RNA binding protein; Retroviridae; chromatin immunoprecipitation; dendritic cells; gel mobility shift assay; gene expression; gene induction /repression; gene interaction; genetic mapping; genetic recombination; green fluorescent proteins; host organism interaction; human tissue; microarray technology; molecular biology information system; polymerase chain reaction; regulatory gene; tissue /cell culture; transcription factor; transfection /expression vector; translation factor; virus infection mechanism; virus replication

DESCRIPTION (provided by applicant): The goal of this proposal is to gain insights into how HIV-1 Tat mediates its effects on host cell gene expression. Tat is among the first genes expressed during HIV-1 infection and is essential for viral gene expression and virus production. Tat increases HIV-1 gene expression by functioning as an elongation factor and interacting with TAR, a RNA sequence present at the beginning of the HIV viral transcripts, and with the host cell factors CDK9 and cyclin T1. The interaction of Tat with these and other host cell transcriptional regulators might be expected to affect host cell gene expression. Indeed, there is considerable evidence that Tat can affect the physiology of T lymphocytes, neurons and antigen presenting cells. Recent studies from our laboratory have shown that the gene expression programs of dendritic cells and macrophages are modified by pathogen exposure and that these modifications can provide important clues to pathogenesis. We have shown that dendritic cell reprogramming by HIV-1 can create conditions that favor virus spread, and that the effect is mediated by the HIV-1 transactivator Tat. This proposal is designed to improve our understanding of the means by which Tat expression causes changes in host cell gene expression in immune cells targeted by HIV-1. To accomplish this, the specific aims of the proposal are 1) To develop a library of adenovirus and retroviral vectors expressing multiple wild type and mutated Tat proteins. 2) To determine the effects of two wild type alleles of Tat on host cell gene expression in immune cells targeted by HIV-1 infection. 3) To map the domain of Tat that is responsible for modifying the host cell gene expression program. 4) To investigate the genome-scale location of the transcription factors STAT1 and IRF7 during Tat expression, as these factors are upregulated by HIV-1 infection and Tat expression. 5) To investigate the mechanism by which Tat reprograms host cell gene expression using genome-scale location analysis experiments designed to detect DNA and RNA binding.

描述（由申请人提供）：本提案的目的是深入了解 HIV-1 Tat 如何介导其对宿主细胞基因表达的影响。 Tat 是 HIV-1 感染期间最先表达的基因之一，对于病毒基因表达和病毒产生至关重要。 Tat 通过充当延伸因子并与 TAR（存在于 HIV 病毒转录本开头的 RNA 序列）以及宿主细胞因子 CDK9 和细胞周期蛋白 T1 相互作用来增加 HIV-1 基因表达。 Tat 与这些和其他宿主细胞转录调节因子的相互作用可能会影响宿主细胞基因表达。事实上，有大量证据表明 Tat 可以影响 T 淋巴细胞、神经元和抗原呈递细胞的生理学。我们实验室最近的研究表明，树突状细胞和巨噬细胞的基因表达程序会因病原体暴露而发生改变，这些改变可以为发病机制提供重要线索。我们已经证明，HIV-1 对树突状细胞进行重编程可以创造有利于病毒传播的条件，并且这种效应是由 HIV-1 反式激活因子 Tat 介导的。该提案旨在加深我们对 Tat 表达导致 HIV-1 靶向免疫细胞中宿主细胞基因表达变化的理解。为了实现这一目标，该提案的具体目标是 1) 开发表达多种野生型和突变 Tat 蛋白的腺病毒和逆转录病毒载体文库。 2) 确定Tat的两个野生型等位基因对HIV-1感染的免疫细胞中宿主细胞基因表达的影响。 3) 绘制负责修饰宿主细胞基因表达程序的Tat结构域。 4) 研究转录因子 STAT1 和 IRF7 在 Tat 表达过程中的基因组规模位置，因为这些因子因 HIV-1 感染和 Tat 表达而上调。 5) 使用旨在检测 DNA 和 RNA 结合的基因组规模定位分析实验来研究 Tat 重新编程宿主细胞基因表达的机制。