Regulation of Interferon Signaling by INI1/hSNF5 During HIV-1 Replication

HIV-1 复制过程中 INI1/hSNF5 干扰素信号传导的调节

• 批准号: 7284646
• 负责人: GANJAM V KALPANA
• 金额: $ 20.75万
• 依托单位: ALBERT EINSTEIN COLLEGE OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-09-30 至 2009-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7284646
• 关键词: Acquired Immunodeficiency Syndrome; Antiviral Agents; Antiviral Response; Binding; Cellular Stress; Class; Complex; Cytoplasm; Development; Event; Future; Gagging; Gene Expression; Gene Expression Profile; Gene Targeting; Genes; Goals; HIV-1; HIV-1 integrase; Health; IFITM1 gene; In Vitro; Integrase; Integration Host Factors; Interferons; Lead; Light; Lymphocyte; Mediating; Monitor; Mutate; Mutation; Natural Immunity; Nuclear; Oncogene Activation; PML gene; Pathogenesis; Pharmaceutical Preparations; Poly I-C; Protein Binding; Proteins; RNA Interference; Regulation; Resistance; Rhabdoid Cell; Rhabdoid Tumor; Right-On; Role; SMARCB1 gene; STAT1 gene; Signal Transduction; Staging; T-Lymphocyte; TP53 gene; Testing; Thinking; Transcriptional Regulation; Transducers; Tumor Suppression; Tumor Suppressor Proteins; Vaccines; Viral; Virion; Virus; Virus Diseases; base; chromatin remodeling; human IFITM1 protein; in vivo; insight; integrase interactor 1; mutant; novel; novel therapeutics; pol genes; response; therapeutic vaccine; virus host interaction

DESCRIPTION (provided by applicant): The long-term goal of this proposal is to delineate the dynamic host-virus interactions during HIV-1 replication and use this information to develop novel and effective strategies to combat AIDS. INI1/hSNF5, is a HIV-1 integrase (IN) binding host factor, is a component of the mammalian chromatin-remodeling SWI/SNF complex involved in transcriptional regulation. INI1/hSNF5 directly and strongly binds to HIV-1 IN and a fragment of INI1/hSNF5, spanning the minimal IN-binding domain, dominant negatively inhibits HIV-1 replication. These observations suggested that INI1/hSNF5 interaction is required for HIV-1 replication. Recent studies demonstrate that INI1/hSNF5 is a tumor suppressor, biallelically mutated in rhabdoid tumors. Our attempt to study global gene expression profile revealed that INI1/hSNF5 stimulates a high degree of IFN signal induced genes (ISGs) and PML nuclear body proteins in INI1-/- rhabdoid cells. These results shed new insight on the role of INI1/hSNF5 in HIV-1 replication. We hypothesize that INI1 is a component of the cellular anti-viral defense (innate immunity) and is required for induction of IFN signaling during HIV-1 replication and that HIV-1 subverts the effect of INI1/hSNF5 by directly binding to it via IN and capturing it during its replication. To test this hypothesis, in the specific aim I we will determine if INI1/hSNF5 is required for inducing IFN signaling in T cells by IFNs, poly(I):(C) and during HIV-1 replication. We will monitor the induction of antiviral genes (e.g. IFIT1, IFITM1, OAS2, MX2 and PKR), PML nuclear body components (e.g. PML, Sp100, Sp110), and signal transducers (e.g. STAT1). We will correlate the effect of down-modulation of INI1 and ISG expression to HIV-1 replication. These results will establish if INI1/hSNF5 is a component of the cellular antiviral defense during HIV-1 replication. In the specific aim II we will determine if HIV-1 subverts the INI1-induced antiviral defense by capturing it via binding by IN. We will: (i) use a mutant HIV-1 virion harboring INI1-interaction-defective IN mutants (H12Y) and a transdominant mutant of INI1 (S6); determine if IN-mutants H12Y will be unable to capture INI1 and allow the IFN signaling; (ii) determine if S6 sequesters IN and allows cellular INI1 to mount IFN signaling and compare the effect S6 to an IN-interaction defective mutant of S6 (E3); (iii) To determine if IN within the context of Gag-Pol is able to sequester INI1, we will investigate the temporal relationship between expression of Gag-Pol, ISG expression and redistribution of endogenous INI1 during late events of HIV-1 replication. If Gag-Pol expression is able to sequester cellular INI1 in the cytoplasm, then this will lead to subversion of the ISG expression during HIV-1 replication. These results will shed light on the mechanism by which HIV-1 may subvert INI1-induced cellular antiviral defense. We hope that together the above two specific aims will establish a new paradigm in dynamic host-HIV-1 interaction and may provide insight for developing novel antiviral and vaccine strategies against AIDS. AIDS is still a major health problem because of the inability of current drugs to eliminate HIV-1 due to the emergence of the resistant viruses. Therefore, there is a dire need for identification of new targets and development of novel therapeutic strategies to combat AIDS. There is a dynamic interaction between host and the virus during pathogenesis. The aim of this application is to test a novel hypotheses that INI1/hSNF5, a cellular protein that binds to one of the HIV-1 proteins (integrase), is a component of the cellular antiviral defense and utilize this insight for developing novel antiviral strategies against AIDS in the future.

描述(由申请人提供)：这项提案的长期目标是描绘HIV-1复制过程中动态的宿主-病毒相互作用，并利用这些信息制定新的和有效的抗击艾滋病的战略。INI1/hSNF5是一种HIV-1整合酶结合宿主因子，是哺乳动物染色质重塑SWI/SNF复合体的组成部分，参与转录调控。INI1/hSNF5直接与HIV-1 IN和INI1/hSNF5片段强结合，INI1/hSNF5跨越最小IN结合域，显性地负向抑制HIV-1复制。这些观察结果表明，HIV-1复制需要INI1/hSNF5相互作用。最近的研究表明，INI1/hSNF5是一种肿瘤抑制基因，在横纹肌样肿瘤中发生双等位突变。我们试图研究INI1/hSNF5的全球基因表达谱，发现INI1/hSNF5在INI1-/-横纹肌样细胞中高度刺激干扰素信号诱导基因(ISGs)和PML核体蛋白。这些结果为INI1/hSNF5在HIV-1复制中的作用提供了新的见解。我们假设INI1是细胞抗病毒防御(先天免疫)的一个组成部分，在HIV-1复制过程中诱导干扰素信号是必需的，而HIV-1通过IN直接与INI1/hSNF5结合并在复制过程中捕获它来破坏INI1/hSNF5的作用。为了验证这一假设，在特定的目标I中，我们将确定是否需要INI1/hSNF5来通过IFN、Poly(I)：(C)在T细胞中诱导干扰素信号以及在HIV-1复制过程中。我们将监测抗病毒基因(例如IFIT1、IFITM1、OAS2、MX2和PKR)、PML核体组件(例如PML、Sp100、Sp110)和信号转导蛋白(例如STAT1)的诱导。我们将把INI1和ISG表达下调与HIV-1复制的影响联系起来。这些结果将确定INI1/hSNF5是否是HIV-1复制过程中细胞抗病毒防御的一个组成部分。在特定的目标II中，我们将确定HIV-1是否通过IN结合捕获它来颠覆INI1诱导的抗病毒防御。我们将：(I)使用含有INI1相互作用缺陷IN突变体(H12Y)和INI1的转显性突变(S6)的HIV-1病毒粒子；确定IN突变体H12Y是否无法捕获INI1并允许干扰素信号；(Ii)确定S6是否隔离IN并允许细胞INI1安装干扰素信号，并将S6的效果与S6的IN-相互作用缺陷突变体(E3)进行比较；(Iii)为了确定Gag-Pol背景下的IN是否能够隔离INI1，我们将研究在HIV-1复制的后期事件中，Gag-Pol的表达、ISG的表达和内源性INI1的重新分布之间的时间关系。如果Gag-Pol的表达能够将细胞内的INI1隔离在细胞质中，那么这将导致HIV-1复制过程中ISG表达的颠覆。这些结果将阐明HIV-1可能破坏INI1诱导的细胞抗病毒防御的机制。我们希望以上两个具体目标的结合将在动态宿主-HIV-1相互作用中建立一个新的范式，并可能为开发新的抗病毒和抗艾滋病疫苗策略提供见解。艾滋病仍然是一个主要的健康问题，因为由于出现了耐药病毒，目前的药物无法消除艾滋病毒-1。因此，迫切需要确定新的目标和开发新的治疗策略来抗击艾滋病。在致病过程中，宿主与病毒之间存在着动态的相互作用。这项应用的目的是检验一种新的假设，即INI1/hSNF5是一种与HIV-1蛋白(整合酶)结合的细胞蛋白，是细胞抗病毒防御的组成部分，并利用这一见解在未来开发抗艾滋病的新抗病毒策略。