Inhibitors Targeting HIV Integrase Multimers

描述(由申请人提供)：对当前抗艾滋病毒药物耐药的艾滋病毒表型的不断出现要求开发具有替代抑制机制的新疗法。HIV整合酶(IN)通常被认为是一个重要的抗病毒靶点，原因如下：它的催化活性是病毒复制所必需的，没有与IN密切相关的细胞等价物，以及特定的IN抑制剂可能对目前可用的治疗方法耐药的病毒株有效。本提案的重点是开发HIV IN多聚体作为新的治疗靶点。我的方法的主要新奇之处在于稳定而不是破坏非活性构象中的IN多聚体。我最近的发现提供了这方面的理论基础，这些发现表明，去连接的IN亚基必须是高度动态和灵活的，才能在病毒DNA存在的情况下形成功能多聚体。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，我报告了一种小分子抑制物(化合物1)，它有效地结合在IN二聚体界面上，并将相互作用的亚基稳定在不活跃的构象中。这些发现使我得出以下假设：HIV IN具有独特的结构口袋，可以被小分子选择性地靶向，通过锁定IN进入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IN二聚体界面上适合与小变构抑制剂结合的两个不同的位置(这里称为“底部”和“侧面”口袋)。目标1将致力于提高化合物1与底部口袋的结合特异性和亲和力；目标2将合理设计新的变构分子，选择性地结合“侧面”口袋。

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.