Design of SMAC Peptidomimetics and Nonpeptidic Mimetics

SMAC 肽模拟物和非肽模拟物的设计

• 批准号: 6908072
• 负责人: SHAOMENG WANG
• 金额: $ 28.23万
• 依托单位: UNIVERSITY OF MICHIGAN AT ANN ARBOR
• 依托单位国家: 美国
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-07-01 至 2008-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6908072
• 关键词: X ray crystallography; antineoplastics; apoptosis; binding proteins; biomimetics; biotechnology; biotherapeutic agent; cysteine endopeptidases; drug design /synthesis /production; enzyme activity; fluorescence polarization; membrane permeability; mitochondria; neoplastic cell; nuclear magnetic resonance spectroscopy; peptide chemical synthesis; pharmacokinetics; protein binding; protein protein interaction; protein structure function

DESCRIPTION (provided by applicant): Smac/DIABLO was recently discovered as a potent pro-apoptotic protein released from mitochondria. Smac functions as an endogenous antagonist for the Inhibitors of Apoptosis Proteins (lAPs) by binding to the BIR3 domain of X-linked lAP (XIAP) and other lAP proteins and displace caspase-9 from this site. High resolution 3D structures of Smac in complex with the BIR3 domain of XIAP showed that the interaction between them is mediated by only four Smac residues at its N-terminus and a small but well-defined binding groove in the XIAP BIR3 domain, which is suitable for designing small molecule inhibitors. Several recent studies have shown that short Smac peptides (4-8 residues) tethered to a carrier peptide for intra-cellular delivery are effective to overcome apoptosis-resistance of cancer cells in vitro and in vivo by directing targeting lAP proteins, while having no toxicity to normal tissues or to animals. Hence, Smac mimetics that bind to the BIR3 domain in XlAP where Smac and caspase-9 bind may have great therapeutic potential to be developed as an entirely new class of anticancer drugs through overcoming apoptosis-resistance of cancer cells as mediated by lAP protein overexpression. In this project, we propose to design, synthesize and characterize highly potent Smac peptido-mimetics and nonpeptidic mimetics with much improved cell permeability over Smac peptides through the following Specific Aims: Aim 1. (a). Structure-based design of Smac peptido-mimetics and nonpeptidic mimetics based upon the published high-resolution experimental structures of Smac in complex with XlAP BIR3. (b). Determination of high-resolution structures of several most potent Smac mimetics through X-ray crystallography. Aim 2. Chemical synthesis of these Smac mimetics designed in Aim 1. Aim 3. (a). Determination of the binding affinities of these Smac mimetics to the BIR3 domain of XIAP by the fluorescence polarization-based method; (b). Conclusive confirmation of the binding of the most potent Smac mimetics to the XlAP BIR3 protein by NMR methods. Aim 4. Investigation of the activity, specificity and molecular mechanisms of action of the most potent Smac mimetics. Designing highly potent and cell-permeable Smac mimetics is a new and exciting area of research. Our current proposed research represents the first but an essential step toward our long-term goal of developing a novel anticancer drug through targeting apoptosis-resistance in cancer cells mediated by lAP proteins.

描述（由申请人提供）：Smac/Diablo最近被发现是一种从线粒体释放的有效的促凋亡蛋白。 SMAC通过与X连锁膝盖（XIAP）和其他LAP蛋白的BIR3结构域结合，充当凋亡蛋白抑制剂（LAP）抑制剂的内源拮抗剂，并从该位点置换了caspase-9。 SMAC与XIAP的BIR3结构域中的高分辨率3D结构表明，它们之间的相互作用是由其N末端的四个SMAC残基介导的，而XIAP BIR3结构域中的小但定义明确的结合凹槽则适用于该结构域，该凹槽适用于设计小分子抑制剂。最近的几项研究表明，短的SMAC肽（4-8个残基）链接到载体肽进行细胞内递送可有效克服癌细胞在体外和体内的凋亡 - 通过指导靶向靶向LAP蛋白，而对正常组织或对动物的毒性无毒性。因此，通过克服LAP蛋白过表达的癌细胞介导的癌细胞抑制癌细胞的抗凋亡 - 抗凋亡抗性，SMAC和CASPASE-9结合在XLAP中与BIR3结构域结合的SMAC模拟物可能具有很大的治疗潜力。在这个项目中，我们建议通过以下特定目的设计，合成和表征高度有效的SMAC SMAC SMAC SMAC肽摄像理和非肽模拟物，其细胞渗透性比SMAC肽的细胞渗透性得到了巨大改善： 目标1。（a）。基于结构的SMAC肽摄影和非肽模拟物的设计基于与XLAP BIR3复合物中发表的高分辨率实验结构。 （b）。通过X射线晶体学确定几种最有效的SMAC模拟物的高分辨率结构。 目标2。在目标1中设计的这些SMAC模拟物的化学合成。目标3。（a）。通过基于荧光极化的方法来确定这些SMAC模拟物与XIAP的BIR3结构域的结合亲和力。 （b）。通过NMR方法对最有效的SMAC模拟物与XLAP BIR3蛋白的结合确认。目标4。对最有效的SMAC模拟物的活性，特异性和分子机制的研究。 设计高度有效且可渗透的SMAC Mimetics是一个新的令人兴奋的研究领域。我们目前提出的研究是朝着我们长期目标迈出的第一步，即通过靶向通过LAP蛋白介导的癌细胞中凋亡的抗性药物来开发新型抗癌药物的第一步。