The molecular mechanism of LCD, a prevalent and conserved non-apoptotic cell death program

项目摘要/摘要 这项拟议研究的长期目标是揭示驱动非凋亡细胞的分子机制。 脊椎动物发育和疾病过程中的死亡。编程细胞死亡功能以塑造器官，重塑 组织，调节细胞数量，去除有缺陷的细胞。而细胞凋亡是研究最多的细胞类型 死亡，这并不能解释发育过程中所有细胞的破坏。对线虫的研究已经 发现了一种新的发育性细胞死亡程序，称为连接细胞类型死亡(LCD)，它是 在形态和分子上与细胞凋亡截然不同。细胞死亡与LCD的特征是常见的观察 在脊椎动物发育过程中以及在患者和小鼠中的神经退行性聚谷氨酰胺模型 疾病。这项建议旨在识别驱动线虫LCD的分子事件，并测试它们的 脊椎动物环境中的功能保护。为了严格调查这些机制，这项F32提案 在脊椎动物和无脊椎动物模型中结合遗传学、显微镜和计算分析方面的培训 研究以下特定目的的系统：1)鉴定泛素蛋白酶体的分子靶标 不间断电源系统(UPS)在线虫液晶显示期间通过执行功能研究和 酵母双杂交筛选；2)通过细胞培养揭示脊椎动物LCD的分子基础 分析，测试线虫LCD基因同源物的作用，并进行全基因组CRISPR/Cas9 在培养的哺乳动物细胞中进行筛选。这里提出的研究将导致新标记的开发 在脊椎动物发育和疾病中区分不同类型的细胞死亡，同时发现 液晶显示器的分子基础。因为LCD是一种流行的细胞死亡类型，所以这一提议可能不会 只是阐明了发育、神经退化和癌症的基本方面，但最终也可能 发现具有临床意义的道路。

Project Summary/ Abstract The long-term goal of the proposed research is to uncover molecular mechanism driving non-apoptotic cell death in vertebrate development and disease. Programed cell death functions to sculpt organs, remodel tissues, regulate cell number, and remove defective cells. While apoptosis is the most studied type of cell death, it does not account for all cellular destruction during development. Studies in C. elegans have uncovered a novel developmental cell death program, referred to as linker cell-type death (LCD), which is morphologically and molecularly distinct from apoptosis. Cell death with LCD features is commonly observed during vertebrate development and in patients and mouse models of neurodegenerative polyglutamine diseases. This proposal seeks to identify molecular events driving LCD in C. elegans, and to test their functional conservation in vertebrate settings. To rigorously investigate these mechanisms, this F32 proposal combines training in genetics, microscopy and computational analysis in vertebrate and invertebrate model systems to investigate the following specific aims: 1) identify molecular targets of the Ubiquitin Proteasome System (UPS) that precipitate cell destruction during LCD in C. elegans by performing functional studies and a yeast 2-hybrid screen; 2) uncover the molecular basis of LCD in vertebrates by developing a cell culture assay, testing roles of homologs of C. elegans LCD genes, and conducting a whole-genome CRISPR/Cas9 screen in cultured mammalian cells. The studies proposed here will lead to the development of new markers to distinguish among different types of cell death in vertebrate development and disease, while uncovering the molecular underpinnings of LCD. Because LCD is a prevalent type of cell demise, this proposal may not only shed light on basic aspects of development, neurodegeneration, and cancer, but could also eventually uncover in-roads of clinical significance.