Caspase-independent cell death and neurodegeneration

描述（由申请人提供）：该项目的总体目标是 描述了一种新的细胞死亡途径，称为“坏死”，并确定 它在神经退行性变中的作用。最近产生了大量证据 多年来表明两种“经典”细胞死亡途径：细胞凋亡和 坏死，不能解释细胞生理和病理的多样性 死亡机制。第三条途径的存在，称为“坏死”，是 提议。该途径在被诱导经历的细胞中被激活 细胞凋亡，但阻止其完成。建议代表 新颖的安全机制旨在消除损坏和潜在的 危险的细胞。坏死与程序性细胞死亡具有相同的性质 细胞凋亡和执行子程序以及坏死的表型特征。 利用高通量筛选几种化学小分子库 分离出坏死抑制剂。这些化合物被发现 选择性抑制坏死，但不抑制细胞凋亡，强调了不同的 坏死细胞死亡过程的机制。使用选定的抑制剂 研究表明，坏死是多种细胞中主要的细胞死亡过程。 体外不依赖半胱天冬酶的细胞死亡范例。还出现了坏死 与 PC12 细胞中的淀粉样蛋白毒性和缺血性脑损伤有关 体内。分析所选抑制剂在各种系统中的效果 表明其中两个针对细胞类型特异性信号传导途径， 而另一种化合物会阻止统一的下游执行步骤，提供 有机会在以下方面描述腱坏死的各个步骤 个体抑制剂。两个坏死调节因子（p38 激酶和组织蛋白酶 B） 被发现了。本研究的具体目的如下： 1 ) 评估 坏死在体外和体内神经元细胞死亡中的作用； 2) 至 表征坏死所涉及的分子事件； 3）识别小说 利用化学、细胞和分子生物学研究参与坏死的基因 接近。 该研究将在哈佛大学细胞生物学系进行 袁俊英博士和Timothy博士联合指导的医学院 米奇森。袁俊英博士是神经元领域公认的领军人物 细胞死亡。 Timothy Mitchison 博士是一位杰出的细胞生物学家， 也是化学生物学方法的先驱之一。袁博士将提供 为前两个目标提供资源和指导，部分为第三个目标。 Timothy Mitchison 博士将提供培训和监督以及 哈佛大学化学与细胞生物学研究所的化学资源 该项目的生物学部分。细胞生物学系全力致力于 申请人发展成为该领域完全独立的研究人员 与衰老相关的神经退行性疾病。 Alexei Degterev 博士立志成为一名完全独立的研究人员 衰老相关神经元细胞死亡领域的科学家，将使用 K01 培训期，发展和提高执行所需的技能 该领域的独立研究并开发研究项目，该项目将来自 为他今后的独立研究打下基础。

DESCRIPTION (provided by applicant): The overall goal of this project is to characterize a novel cell death pathway, termed "aponecrosis", and determine its role in neurodegeneration. Extensive evidence was generated in recent years suggesting that two "classic" cell death pathways, apoptosis and necrosis, do not explain the variety of physiological and pathological cell death mechanisms. Existence of the third pathway, termed "aponecrosis", is proposed. This pathway is activated in cells that are induced to undergo apoptosis, yet prevented from its completion. It is proposed to represent a novel safety mechanism aimed at elimination of damaged and potentially dangerous cells. Aponecrosis shares programmed cell death nature with apoptosis and execution subroutines and phenotypic features with necrosis. Using high throughput screening of small molecule library several chemical inhibitors of aponecrosis were isolated. These compounds were found to selectively inhibit aponecrosis, but not apoptosis, underscoring distinct mechanism of the aponecrotic cell death process. Using selected inhibitors aponecrosis was shown to represent a major cell death process in a variety of caspase-independent cell death paradigms in vitro. Aponecrosis was also implicated in amyloid-beta toxicity in PC12 cells and ischemic brain damage in vivo. Analysis of the effects of selected inhibitors in various systems suggests that two of them target cell type specific signaling pathways, whereas another compound blocks uniform downstream execution step, providing the opportunity to characterize various steps in aponecrosis with the help of individual inhibitors. Two aponecrotic regulators (p38 kinase and cathepsin B) were discovered. Specific aims of this study are as follows: 1 ) To evaluate the role of aponecrosis in neuronal cell death in vitro and in vivo; 2) To characterize molecular events involved in aponecrosis; 3) To identify novel genes involved in aponecrosis using chemical, cell and molecular biology approaches. The research will be conducted in the Department of Cell Biology at Harvard Medical School under the joint guidance of Dr. Junying Yuan and Dr. Timothy Mitchison. Dr. Junying Yuan is a recognized leader in the field of neuronal cell death. Dr. Timothy Mitchison is an outstanding cell biologist, who is also one of the pioneers of chemical biology approach. Dr. Yuan will provide resources and mentorship for the first two and partially for the third aim. Dr. Timothy Mitchison will provide training and supervision as well as resources of Harvard Institute of Chemistry and Cell Biology for the chemical biology part of the project. Department of Cell Biology is fully committed to the applicant's development into a fully independent researcher in the field of aging-related neurodegeneration. Dr. Alexei Degterev is aspiring to become a fully independent research scientist in the field of aging-associated neuronal cell death and would use K01 training period to develop and enhance the skills needed to perform independent research in this area and develop research project that will from the basis for his future independent research.