Targeting Apoptosis by Chemical Design

描述（由申请人提供）： 细胞凋亡是细胞响应特定的内部和外部信号而自我毁灭的精心策划的过程。 程序性细胞死亡受蛋白质“BCL-2家族”控制的复杂制衡网络调节。 细胞凋亡途径的基因调控是多种血液病和其他疾病发病机制中的重要事件。 BCL-2是一种存活蛋白，其过量产生促进病理性细胞存活/死亡。 触发线粒体凋亡的特定分子编排仍然未知。 Bid的结构由8个α-螺旋定义，其中一个是关键的死亡效应螺旋。 我们假设BID内的特定α-螺旋结构域参与有助于其整体功能的不同相互作用。 本研究的目的是融合化学和生物学技术来阐明BID诱导细胞凋亡的机制，并开发出在体内调控细胞凋亡的分子。 因此，本提案的具体目的是：1）合成和表征BID的稳定化α螺旋（SAHB），2）定义BID的α-螺旋结构域在触发线粒体凋亡中的作用，以及3）利用SAHB来验证和操纵培养细胞和小鼠模型中的BID活性。 已经合成了在BID的死亡效应螺旋之后建模的SAHB的初步小组。 与未修饰的肽相比，这些SAHB中的两种证明：（a）α-螺旋度增加超过5倍;（B）蛋白酶抗性增强高达3.5倍;（c）线粒体细胞色素c释放（细胞凋亡的关键步骤）的效力增加高达25倍;和（d）培养的Jurkat细胞中的细胞凋亡诱导。 SAHB具有双重潜力，既可作为剖析凋亡途径的生物学工具，又可作为以异常细胞低或增生为特征的疾病的原型治疗剂。 由国际公认的导师，合作者和顾问组成的多元化团队，在合成化学，结构生物学，凋亡生物学和临床血液学/肿瘤学领域拥有专业知识，将为Walensky博士的发展提供一个理想的培训环境作为这些领域的独立研究者。

DESCRIPTION (provided by applicant): Apoptosis is the orchestrated process by which cells self-destruct in response to specific internal and external signals. Programmed cell death is regulated by a complex network of checks and balances governed by the "BCL-2 family" of proteins. Faulty regulation of apoptotic pathways is a seminal event in the pathogenesis of a variety of hematologic and other diseases. BCL-2 is a survival protein, and its overproduction facilitates pathologic cell survival death. The specific molecular choreography that triggers mitochondrial apoptosis remains unknown. Bid's structure is defined by 8 alpha-helices, one of which is a critical death effector helix. We hypothesize that specific alpha-helical domains within BID engage in distinct interactions that contribute to its overall function. The goal of this research is to fuse chemical and biological techniques to elucidate the mechanism of BID-induced apoptosis and develop molecules to manipulate apoptosis in vivo. Thus, the specific aims of this proposal are: 1) Synthesize and characterize Stabilized Alpha Helices of BID (SAHBs), 2) Define the role(s) of BID's alpha-helical domains in triggering mitochondrial apoptosis, and 3) Utilize SAHBs to validate and manipulate BID activities in cultured cells and mouse models. A preliminary panel of SAHBs modeled after BID's death effector helix has been synthesized. Compared to unmodified peptide, two of these SAHBs demonstrate: (a) more than 5-fold increase in alpha-helicity; (b) up to 3.5-fold enhancement in protease resistance; (c) up to 25-fold increased potency in mitochondrial cytochrome c release, a key step in apoptosis; and (d) apoptosis induction in cultured Jurkat cells. SAHBs have the dual potential to serve as biological tools to dissect apoptotic pathways, and as prototype therapeutics for diseases characterized by aberrant cellular hypo- or hyperplasia. A diverse team of internationally recognized mentors, collaborators, and advisors with expertise in the fields of synthetic chemistry, structural biology, apoptosis biology, and clinical hematology/oncology will provide an idea training environment for Dr. Walensky's development as an independent investigator at the interface of these notable fields.