Inhibitors Targeting HIV Integrase Multimers

描述（由申请人提供）：对当前抗HIV药物耐药的HIV表型的不断出现表明需要开发具有替代抑制机制的新疗法。HIV整合酶（IN）通常被视为重要的抗病毒靶点，原因如下：它的催化活性是病毒复制所必需的，没有与IN密切相关的细胞等效物，并且特异性IN抑制剂可能对抵抗当前可用疗法的病毒株有效。目前的建议集中于利用HIV IN多聚体作为新的治疗靶点。我的方法的主要新奇是稳定，而不是不稳定的非活性构象的IN多聚体。我最近的发现提供了这样做的基本原理，这些发现表明，在病毒DNA存在下，为了形成功能性多聚体，未配体的IN亚基必须是高度动态和灵活的。限制IN的灵活性会对其催化活性产生不利影响。作为原理的证明，我已经报道了一种小分子抑制剂（化合物1），其有效地结合在IN二聚体界面处并将相互作用的亚基稳定为非活性构象。这些发现使我产生了以下假设：HIV IN具有独特的结构口袋，可以被小分子选择性地靶向，通过将IN锁定为非生产性多聚体状态来抑制病毒整合。为了解决这一假设，我的初步研究已经确定了两个独立的网站（这里被称为“底部”和“侧”口袋）在IN二聚体接口适合结合的小变构抑制剂。目标1将致力于增加化合物1对“底部”口袋的结合特异性和亲和力;目标2将合理设计选择性结合“侧部”口袋的新的变构分子。 公共卫生相关性：出现对当前抗逆转录病毒疗法耐药的HIV-1毒株是一个严重的临床问题。因此，迫切需要鉴定和验证用于药物发现的新病毒靶点。在本建议中研究的一个这样的目标是一个关键的HIV-1酶整合酶的多聚体结构。

DESCRIPTION (provided by applicant): The continuous emergence of HIV phenotypes resistant to the current anti-HIV drugs dictates a need to develop new therapies with alternative mechanisms of inhibition. HIV integrase (IN) is commonly viewed as an important antiviral target for the following reasons: its catalytic activities are required for viral replication, there is no closely related cellular equivalent of IN, and specific IN inhibitors are likely to be effective against viral strains resistant to currently available therapies. The present proposal focuses on exploiting HIV IN multimers as a new therapeutic target. The main novelty of my approach is to stabilize rather than destabilize IN multimers in the inactive conformation. The rationale for this has been provided by my recent findings which demonstrated that unliganded IN subunits have to be highly dynamic and flexible in order to form functional multimers in the presence of viral DNA. Restricting IN flexibility adversely affects its catalytic activities. As a proof of principle I have reported a small molecule inhibitor (compound 1) that effectively binds at the IN dimer interface and stabilizes interacting subunits into an inactive conformation. These findings led me to the following hypothesis: HIV IN possesses unique structural pockets that can be selectively targeted by small molecules to inhibit viral integration by locking IN into an unproductive multimeric state. To address this hypothesis, my preliminary studies have identified two separate sites (which are termed here as "bottom" and "side" pockets) at the IN dimer interface suitable for binding of small allosteric inhibitors. Aim 1 will focus to increase the binding specificity and affinity of compound 1 for the "bottom" pocket; aim 2 will rationally design new allosteric molecules selectively binding the "side" pocket. PUBLIC HEALTH RELEVANCE: Emergence of HIV-1 strains resistant to the current antiretroviral therapies is a serious clinical problem. Therefore, there is an urgent need to identify and validate new viral targets for drug discovery. One such target investigated in the present proposal is a multimeric structure of a key HIV-1 enzyme integrase.