The regulation and targeting of cell survival pathways in cancer

项目摘要/摘要 自噬的细胞循环过程是肿瘤细胞生存和适应 各种应激，包括缺血和化疗，最终导致更多 侵袭性肿瘤生长和化疗耐药性。众所周知，ATG9A在驾驶过程中起着主导作用 肿瘤细胞自噬，但我们对ATG9A是如何调控的理解存在根本差距 2)蛋白质-蛋白质相互作用如何介导ATG9A动员到 促进自噬；以及3)将ATG9A功能缺陷与人类疾病联系起来的机制， 包括癌症。这些缺口阻碍了阻断肿瘤细胞的靶向治疗的合理设计 自噬。长期目标是发现肿瘤细胞存活的机制，并开发有针对性的 基于这些机制的策略，以利用癌细胞的脆弱性 本研究旨在阐明ATG9A介导的自噬调控的详细机制。这个 中心假说是，在ULK1中，ATG9A的磷酸化受到AMPK的正调控 复杂的和负调控的营养敏感的磷酸酶，控制其动员 并向自噬小体贩运。此外，我们的数据揭示了ATG9A新的相互作用 通过LRBA和ULK1非依赖的ATG13亚复合体，我们建议规范ATG9A的贩运 在自噬中。特别是，我们假设ATG9A和LRBA之间的相互作用在 携带LRBA突变的患者，这可能解释了这些突变是如何导致免疫缺陷的 和B细胞淋巴瘤。在初步数据的指导下，这一假设将在以下方面进行检验 具体目标：目标1：确定ATG9A的磷酸化机制及其对ATG9A的影响 贩卖人口。目的2：确定不依赖于ULK1的ATG13亚复合体的机制 调节ATG9A。目标3：确定LRBA是否调节ATG9A，以及是否致病 在自噬中，LRBA的突变扰乱了ATG9A的功能。这项提议是创新的，因为它 阐明ATG9A调节的新概念/模型并应用新兴技术(14-3-3 磷酸探针，BioID)，以克服研究ATG9A的内在挑战。建议数 研究意义重大，因为它填补了我们对最小的- 理解自噬调节因子ATG9A，并阐明有缺陷的ATG9A的潜在作用 对人类疾病的监管。

PROJECT SUMMARY/ABSTRACT The cellular recycling process of autophagy is essential for tumor cells to survive and adapt to a variety of stresses, including ischemia and chemotherapies, which ultimately leads to more aggressive tumor growth and chemoresistance. ATG9A is known to play a governing role in driving tumor cell autophagy, yet fundamental gaps exist in our understanding of 1) how ATG9A is regulated post-transcriptionally; 2) how protein-protein interactions mediate the mobilization of ATG9A to promote autophagy; and 3) mechanisms that link defective ATG9A function to human diseases, including cancer. These gaps hinder the rational design of targeted therapies to block tumor cell autophagy. The long-term goal is to discover mechanisms of tumor cell survival and develop targeted strategies, based on these mechanisms, to exploit cancer cell vulnerabilities The overall objective of this proposal is to elucidate a detailed mechanism of ATG9A-mediated regulation of autophagy. The central hypothesis is that ATG9A phosphorylation is positively regulated by AMPK within the ULK1 complex and negatively regulated by a nutrient sensitive phosphatase, which control its mobilization and trafficking toward the autophagosome. In addition, our data revealed novel ATG9A interactions with LRBA and an ULK1-independent ATG13 subcomplex that we propose regulate ATG9A trafficking in autophagy. In particular, we posit that the interaction between ATG9A and LRBA is defective in patients carrying LRBA mutations, which may explain how these mutations cause immunodeficiency and B cell lymphoma. Guided by preliminary data, this hypothesis will be tested in the following specific aims: Aim 1: Determine the mechanism of ATG9A phosphorylation and its impact on ATG9A trafficking. Aim 2: Determine the mechanism by which an ULK1-independent ATG13 subcomplex regulates ATG9A. Aim 3: Determine if LRBA regulates ATG9A and whether disease-causing mutations in LRBA disrupt ATG9A function in autophagy. The proposal is innovative because it elucidates novel concepts/models of ATG9A regulation and applies emerging techniques (14-3-3 phospho-probing, BioID) to overcome the inherent challenges of studying ATG9A. The proposed research is significant because it fills fundamental gaps in our understanding of one of the least- understood autophagy regulators, ATG9A, and elucidates a potential role for defective ATG9A regulation in human disease.