Chemical Inhibitors of the Proteasomal ATPases

蛋白酶体 ATP 酶的化学抑制剂

基本信息

批准号：
7905124
负责人：
Thomas J. Kodadek
金额：
$ 38.14万
依托单位：
SCRIPPS FLORIDA
依托单位国家：
美国
项目类别：
财政年份：
2009
资助国家：
美国
起止时间：
2009-08-01 至 2011-07-31
项目状态：
已结题

项目摘要

Proteasome inhibitors are now one of the first treatment options for multiple myeloma and are being evaluated in clinical trials against a variety of other cancers. However, these compounds, which target one of the three active sites of the proteasome, have drawbacks including side effects and emerging resistance. Therefore, it is important to develop and evaluate novel classes of proteasome inhibitors. Recently, we reported the discovery and characterization of the first pharmacological inhibitor of one of the ATPases of the 26S proteasome. These six different AAA class ATPases (called Rpts 1-6) are located at the base 19S regulatory particle (RP) that caps each end of the barrel-like 20S core particle (CP) of the proteasome. The ATPases constitute a protein unwinding activity that acts to introduce substrates into the catalytic interior of the 20S CP and also holds open a flap at the entrance that otherwise impedes substrate access. However, little is known about the contribution of each protein to the ATP-dependent unfolding process. Recent studies in yeast, many from our own laboratory, have also shown that these proteins play important, non-proteolytic roles in RNA polymerase II transcription, DNA repair and perhaps DNA replication. The individual contributions of each of the six ATPases to all of these activities are unclear. In this proposal, we intend to identify and optimize peptoid inhibitors of each of the six proteasomal ATPases. Large peptoid libraries will be synthesized and screened to identify hits using procedures and assays developed for the inhibitor mentioned above, which targets Rpt4. Rapid optimization procedures will be developed to improve the hits into nM leads. These compounds will then be utilized to determine if the proteasomal ATPases play a critical role in mammalian transcription, as is the case in yeast. The isolation of potent inhibitors of these proteins will then set the stage for future biochemical experiments to dissect the role of each protein in various steps in transcription and proteolysis. Future experiments would also include testing their activity in various mouse models of cancer.

蛋白酶体抑制剂现在是多发性骨髓瘤的首选治疗选择之一并正在针对多种其他癌症的临床试验中进行评估。然而，这些化合物针对蛋白酶体的三个活性位点之一，具有缺点包括副作用和新出现的耐药性。因此，重要的是开发和评估新型蛋白酶体抑制剂。最近，我们报道了第一个药理学的发现和表征 26S 蛋白酶体的一种 ATP 酶的抑制剂。这六种不同的AAA级 ATP 酶（称为 Rpts 1-6）位于 19S 调节颗粒 (RP) 的底部，该颗粒覆盖蛋白酶体的桶状 20S 核心颗粒 (CP) 的两端。 ATP酶构成蛋白质解旋活性，其作用是将底物引入催化 20S CP 的内部，并在入口处打开一个挡板，否则会妨碍基底访问。然而，人们对每种蛋白质的贡献知之甚少。 ATP依赖性展开过程。最近对酵母的研究，许多来自我们自己实验室还表明，这些蛋白质在以下过程中发挥着重要的非蛋白水解作用： RNA 聚合酶 II 转录、DNA 修复，或许还有 DNA 复制。这六种 ATP 酶对所有这些活动的各自贡献尚不清楚。在本提案中，我们打算识别并优化六种肽中的每一种的类肽抑制剂蛋白酶体ATP酶。将合成并筛选大型肽库使用为上述抑制剂开发的程序和测定来识别命中，它的目标是 Rpt4。将开发快速优化程序以提高点击率转化为 nM 引线。然后将利用这些化合物来确定蛋白酶体是否 ATP 酶在哺乳动物转录中发挥着关键作用，在酵母中也是如此。这些蛋白质的有效抑制剂的分离将为未来奠定基础生化实验来剖析每种蛋白质在不同步骤中的作用转录和蛋白水解。未来的实验还将包括测试它们的活性在各种癌症小鼠模型中。