Dysregulation of Mitochondrial Dynamics in Sepsis

脓毒症线粒体动力学失调

• 批准号: 10611328
• 负责人: Bereketab Haileselassie
• 金额: $ 24.89万
• 依托单位: STANFORD UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-04-01 至 2024-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10611328
• 关键词: Animal Model; Apoptosis Regulation Gene; Automobile Driving; Autophagosome; Biology; CRISPR/Cas technology; Cell Culture Techniques; Cell Line; Chemicals; Child; Clinical; Co-Immunoprecipitations; Confocal Microscopy; Critically ill children; Data; Development; Diagnostic; Dynamin; Enzymes; Failure; Financial Hardship; Fluorescence Resonance Energy Transfer; Functional disorder; Future; Goals; Healthcare; Hospital Costs; Knockout Mice; Knowledge; Link; Literature; MDM2 gene; Maintenance; Mediating; Mediator; Methods; Mitochondria; Modeling; Multiple Organ Failure; Mus; Nuclear; Organ; Organ failure; Outcome; Oxidative Stress; Parkin; Pathologic; Pathway interactions; Pattern; Peptides; Phase; Phosphorylation; Physicians; Play; Process; Protein Isoforms; Proteins; Repression; Role; Scientist; Sepsis; Sequence Homology; Site; Site-Directed Mutagenesis; Small Interfering RNA; Societies; Syndrome; System; TANK-binding kinase 1; TP53 gene; Technical Expertise; Testing; Training Programs; United States; Work; catalyst; conditional knockout; drug discovery; efficacy testing; experimental study; improved; inhibitor; mimetics; mitochondrial autophagy; mitochondrial dysfunction; mitochondrial membrane; mortality; neonate; novel; peptidomimetics; pifithrin; preservation; prevent; rational design; recruit; septic; skills; targeted treatment; therapeutic target; ubiquitin-protein ligase

Project Summary While recent literature suggests that p53, a regulator of apoptosis, is crucial in the development of sepsis- induced mitochondrial failure, the mechanistic underpinnings behind this finding are not clearly delineated. My preliminary studies have demonstrated that sepsis mediated mitochondrial localization of p53 propagates mitochondrial failure by interacting with dynamin-related protein 1 (Drp1) and promoting Drp1- fission 1 (Fis1) mediated mitochondrial fragmentation. Furthermore, increased mitochondrial localization of p53 in sepsis leads to an accumulation of damaged mitochondria by interacting with, and blocking, key mediators of mitophagy (process necessary for clearance of damaged mitochondria). Importantly, when p53 accumulation is blocked in a cell culture model of sepsis, Drp1 activation is decreased, excessive mitochondrial fission is abrogated and mitochondrial function is rescued. Taken together, my findings suggest that mitochondrial localization of p53 contributes significantly to mitochondrial failure by promoting excessive fission and dysfunctional mitophagy. However, the mechanism through which p53 interacts with key mediators of fission and mitophagy is not clearly understood. Accordingly, using cutting edge methods in chemical biology, this project will: 1) characterize the interaction site between p53 and key mediators of pathologic fission and mitophagy and 2) develop rationally designed peptides that abrogate the pathologic effects of p53 on the mitochondria. To achieve these goals proposed aims of this project are: AIM 1 (K99): Characterize the direct and indirect role of Drp1 on sepsis mediated p53 stabilization and mitochondrial localization. AIM 2 (R00): Determine the consequences of p53 localization patterns on sepsis induced mitophagy and characterize the interaction site between p53 and key mediators of mitophagy. , the AIM 3 (R00): Develop novel protein-protein inhibitors that interfere with pathologic interaction between p53 and mitochondria in sepsis. The proposed project is significant as it will reveal novel mechanistic pathways which contribute to end organ failure in sepsis by defining the link between excessive p53 activation and altered mitochondrial fission and mitophagy. Furthermore, this project aligns with my long-term goal to become an independent physician scientist, identifying therapeutic targets in mitochondrial pathways which abrogate sepsis-induced end organ failure in children. The training program in the K99-phase will further my technical skills and knowledge in chemical biology (aim 1). The proposed R00-phase will provide novel information regarding mitochondrial adaptors of p53 and develop rationally designed peptides that inhibit pathologic p53 - mitochondria interactions (aim 2&3).

项目摘要 虽然最近的文献表明，细胞凋亡调节因子P53在脓毒症的发生发展中起着至关重要的作用。 导致线粒体衰竭，但这一发现背后的机制基础并没有清楚地描绘出来。我的 初步研究表明，脓毒症介导的P53的线粒体定位可以 与动力蛋白相关蛋白1(Drp1)相互作用并促进Drp1-Fis1发生的线粒体衰竭 介导的线粒体碎裂。此外，脓毒症导联中P53的线粒体定位增加 通过与吞丝分裂的关键介质相互作用和阻断而导致受损线粒体的积累 (清除受损线粒体所需的过程)。重要的是，当P53的积累被阻止在 一种脓毒症的细胞培养模型，DRp1活性降低，线粒体过度分裂被取消，并 线粒体功能被挽救了。综上所述，我的发现表明，p53的线粒体定位 通过促进过度的分裂和功能失调的有丝分裂，极大地导致线粒体功能衰竭。 然而，P53与分裂和有丝分裂的关键介体相互作用的机制尚不清楚 明白了。因此，利用化学生物学的尖端方法，本项目将：1)表征 P53与病理性分裂和有丝分裂关键介质的相互作用部位及2)合理发展 设计了消除P53对线粒体的病理影响的多肽。为了实现这些目标 该项目的拟议目标是： 目的1(K99)：鉴定Drp1在脓毒症中直接和间接作用于P53的稳定和 线粒体定位。 目的2(R00)：确定P53定位模式在脓毒症诱导的有丝分裂和 描述P53与丝裂原吞噬的关键介质之间的相互作用部位。 vt.的. 目标3(R00)：开发新的蛋白质-蛋白质抑制剂，干扰P53和P53之间的病理相互作用 脓毒症中的线粒体。 这项拟议的项目意义重大，因为它将揭示有助于末端器官的新的机械途径。 通过确定P53过度激活和线粒体分裂改变之间的联系以及 有丝分裂。此外，这个项目符合我成为一名独立内科科学家的长期目标， 在线粒体通路中寻找治疗靶点以消除脓毒症所致的终末器官衰竭 孩子们。K99阶段的培训计划将加深我在化学生物学方面的技术技能和知识 (目标1)。建议的R00期将提供关于P53和P53的线粒体接头的新信息 开发合理设计的抑制病理性P53-线粒体相互作用的多肽(目标2和3)。