The mechanism and regulation of autophagy

自噬代表细胞稳态的复杂途径，在细胞保护中发挥作用，但如果 失调会导致细胞死亡；完整的监管知识对于潜在的调制至关重要 这个过程用于治疗目的，并增加我们对膜动力学和 细胞器生物发生。自噬发生在所有真核生物中，自噬的蛋白质成分 从酵母到哺乳动物，机器都是保守的。这一过程的特点是双 膜胞质囊泡，自噬体，含有被隔离的细胞质成分 吞噬细胞，一种独特的瞬时隔室。完成后，自噬体与 溶酶体/液泡释放被分解的内囊泡，从而允许进入货物。自噬 在各种发育过程中发挥作用，并与一系列病理生理学相关 条件。该提案的长期目标是了解自噬的作用机制 相关蛋白质、该过程如何调节以及为什么特定突变会导致人类疾病。 在过去的 20 年里，我们对自噬的分子方面有了很多了解——42 自噬—— 相关（Atg）蛋白已被鉴定，但我们对其功能仅具有粗略的了解。此外， 自噬功能障碍与人类多种疾病有关，包括癌症、心脏病和 神经变性。尽管自噬主要具有细胞保护作用，但过度自噬是有害的。因此， 我们需要充分了解监管网络，以便应用旨在治疗的治疗干预措施 通过自噬调节来治疗疾病。未来五年，我们要（1）了解结构 Atg 蛋白的功能； (2) 定义允许自噬诱导的调控控制，确定 特异性和非特异性自噬类型之间的切换，并将自噬维持在适当的水平 级别； (3) 破译影响自噬的突变与疾病之间的关系 最终目标是促进治疗。我们正在利用酵母来研究其分子机制 自噬；这是对这一复杂过程进行分子遗传和生化分析的最佳系统。 然而，由于高度保守，我们从酵母中学到的信息将适用 到更复杂的真核生物。 该提案中描述的实验很重要，因为它们将阐明重要的联系 在上游调控组件和进行自噬的机制之间，提供下一个 将信号转导元件与功能装置联系起来的综合分析步骤， 提高我们对基础细胞生物学的了解，并确定最终治疗干预的目标。 拟议的研究具有创新性，因为它提供了新的、在某些情况下甚至是范式转变的、 有关自噬的调节和功能成分的信息。

Autophagy represents a complex pathway of cellular homeostasis that functions in cytoprotection, but if dysregulated can cause cell death; a complete knowledge of regulation is critical for the potential modulation of this process for therapeutic purposes, and to increase our basic understanding of membrane dynamics and organelle biogenesis. Autophagy occurs in all eukaryotes, and the protein components of the autophagic machinery are conserved from yeast to mammals. The hallmark of this process is the formation of double- membrane cytosolic vesicles, autophagosomes, that contain cytoplasmic components sequestered by the phagophore, a unique transient compartment. After completion, the autophagosomes fuse with the lysosome/vacuole to release the inner vesicle that is broken down, allowing access to the cargo. Autophagy plays a role in various developmental processes and is associated with a range of pathophysiological conditions. The long-term goals of this proposal are to understand the mechanism of action of the autophagy- related proteins, how the process is regulated, and why specific mutations result in human disease. In the last 20 years, we have learned much about the molecular aspects of autophagy—42 autophagy- related (Atg) proteins have been identified, but we only have a cursory knowledge of their function. In addition, autophagic dysfunction is associated with numerous diseases in humans, including cancer, heart disease and neurodegeneration. Although autophagy is primarily cytoprotective, excessive autophagy is detrimental. Thus, we need a full understanding of the regulatory network in order to apply therapeutic interventions aimed at treating disease through autophagy modulation. In the next five years, we want to (1) understand the structure and function of the Atg proteins; (2) define the regulatory controls that allow autophagy induction, determine the switch between specific and non-specific types of autophagy, and maintain autophagy at appropriate levels; and (3) decipher the relationship between mutations affecting autophagy and diseases, with an ultimate goal of facilitating treatment. We are using yeast to investigate the molecular mechanism of autophagy; this is the best system for a molecular genetic and biochemical analysis of this complex process. Because of the high degree of conservation, however, the information we learn from yeast will be applicable to more complex eukaryotes. The experiments described in this proposal are significant because they will elucidate important links between upstream regulatory components and the machinery that carries out autophagy, providing the next step in a comprehensive analysis that links the signal transduction elements to the functional apparatus, advancing our knowledge of basic cell biology, and identifying targets for ultimate therapeutic intervention. The proposed research is innovative, because it is providing new, and in some cases paradigm-shifting, information about the regulatory and functional components of autophagy.