A K63-Ubiquitination Dependent Necroptosis Signaling Network in the Heart

心脏中 K63 泛素化依赖性坏死性凋亡信号网络

• 批准号: 10090946
• 负责人: Qinghang Liu
• 金额: $ 38.88万
• 依托单位: UNIVERSITY OF WASHINGTON
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-01-08 至 2025-12-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10090946
• 关键词: Ablation; Acute; Address; Adult; Apoptosis; Attenuated; Biological; Cardiac; Cardiac Myocytes; Caspase; Cell Death Signaling Process; Cell membrane; Cessation of life; Complex; Data; Dilated Cardiomyopathy; Disease; Enzymes; Gene Transfer; Genetic; Goals; Heart; Heart Injuries; Heart failure; Investigation; Link; MAP3K7 gene; Mediating; Mitochondria; Modeling; Molecular; Mus; Myocardial; Myocardial Ischemia; Necrosis; Organelles; Pathologic; Pathway interactions; Phosphorylation; Physiology; Pilot Projects; Play; Polyubiquitination; Process; RIPK1 gene; RIPK3 gene; Regulation; Reperfusion Injury; Role; Signal Transduction; Swelling; TNF receptor-associated factor 2; TNFRSF1A gene; TRAF2 gene; Testing; Therapeutic; Ubiquitination; cardioprotection; experimental study; gain of function; in vivo; insight; ischemic injury; myocardial injury; novel; overexpression; prevent; receptor; therapeutic target; ubiquitin ligase; ubiquitin-protein ligase; vector

Project Summary/Abstract Loss of cardiomyocytes by apoptosis and/or necrosis is a hallmark of cardiac ischemic injury, pathological remodeling, and end-stage heart failure. Although necrosis was traditionally regarded as a passive and unregulated process, emerging evidence has shifted this paradigm and identified several forms of “programmed necrosis”, including death receptor-mediated necrosis (termed “necroptosis”), mitochondria-mediated necrosis, and other regulated necrotic processes. Despite recent progress, how necroptosis is regulated in the heart remain largely unknown and preventing necroptotic cardiomyocyte death is still an important challenge. Our pilot studies identified a new K63-linked polyubiquitination (K63-Ub) dependent necroptosis signaling network that critically regulates cardiac ischemic injury and pathological remodeling. Intriguingly, the K63-deubiquitinase CYLD (cylindromatosis) was markedly up-regulated, whereas the E3 ubiquitin ligase TRAF2 (TNF receptor associated factor-2) was down-regulated, in the heart after ischemia-reperfusion injury. Our preliminary results further identified CYLD and TRAF2 as an activator and a suppressor of myocardial necroptosis, respectively. Importantly, cardiomyocyte-specific ablation of CYLD attenuated ischemic injury and adverse remodeling by inhibiting necroptosis. Acute deletion of TRAF2 in the adult heart caused dilated cardiomyopathy by promoting necroptosis, whereas TRAF2 gene transfer elicited cardioprotection. Mechanistically, we propose a new K63- Ub dependent necroptotic regulatory mechanism whereby CYLD deubiquitinates TRAF2 and TAK1, disrupts TAK1-RIP1 interaction, and promotes the necroptotic complex. As an opposing mechanism, TRAF2 acts as an E3 ligase for TAK1 to inhibit necroptosis signaling. Thus, the reversible K63-Ub (mainly non-proteolytic) constitutes a new paradigm of necroptosis signaling with important biological implications. We hypothesize that the deubiquitinase CYLD, in conjunction with the E3 ligase TRAF2, critically regulate myocardial necroptosis, ischemic injury, and remodeling, thus representing promising therapeutic targets. Aim 1 will investigate the opposing roles of K63-Ub modifying enzymes CYLD and TRAF2 in regulating myocardial necroptosis and ischemic injury in vivo. Aim 2 will define a CYLD/TRAF2 mediated, K63-Ub dependent necroptosis signaling network in cardiomyocytes. Using genetic and molecular strategies, we will investigate the opposing roles of CYLD and TRAF2 in regulating myocardial necroptosis under basal conditions and in the setting of ischemic injury. The proposed studies will provide new insights into the molecular regulation and functional significance of necroptosis in the heart, which has important translational implications, especially given our preliminary results revealing CYLD/TRAF2 as key necroptotic regulators and promising targets for ischemic heart disease.

项目摘要/摘要 凋亡和/或坏死因心脏缺血性损伤的标志，病理学的标志 重塑和终阶段的心力衰竭。尽管坏死在传统上被视为被动和 不受管制的过程，新兴的证据改变了这一范式，并确定了几种形式的“编程 坏死”，包括死亡受体介导的坏死（称为“坏死”），线粒体介导的坏死， 和其他受调节的坏死过程。尽管最近进展，但在心脏中如何调节坏死性 保持未知，防止坏死性心肌细胞死亡仍然是一个重要的挑战。我们的飞行员 研究确定了一个新的K63连接的多泛素化（K63-UB）依赖性坏死信号网络 批判性调节心脏缺血性损伤和病理重塑。有趣的是，K63-脱硫酸酶 CYLD（cylindromatisois）明显上调，而E3泛素连接酶TRAF2（TNF受体） 相关因子-2）在缺血再灌注损伤后心脏中下调。我们的初步结果 进一步将CYLD和TRAF2鉴定为心肌坏死的激活剂和抑制因子。 重要的是，通过缺血性损伤和不良重塑的Cyld衰减的心肌细胞特异性消融 抑制坏死性。成人心脏中TRAF2的急性缺失通过促进引起了扩张的心肌病 坏死性，而TRAF2基因转移引起心脏保护。从机械上讲，我们提出了一个新的K63- UB依赖性坏死调节机制，Cyld Deupipirination Traf2和Tak1破坏了 tak1-rip1相互作用，并促进坏死复合物。作为一种相反的机制，Traf2充当 tak1的E3连接酶抑制坏死信号传导。这是可逆的K63-UB（主要是非蛋白水解） 构成具有重要生物学意义的坏死信号传导的新范式。我们假设 去泛素酶CYLD与E3连接酶TRAF2结合进行了严重调节的心肌坏死病 缺血性损伤和重塑，从而代表了有希望的治疗靶标。 AIM 1将调查 K63-UB修饰酶Cyld和Traf2在控制心肌坏死和 体内缺血性损伤。 AIM 2将定义CYLD/TRAF2介导的K63-UB依赖性坏死信号传导 心肌细胞的网络。使用遗传和分子策略，我们将研究 CYLD和TRAF2在基本条件下控制心肌坏死和缺血的环境 受伤。拟议的研究将为分子调节和功能意义提供新的见解 心脏中的坏死性，具有重要的翻译意义，特别是考虑到我们的初步结果 将CYLD/TRAF2揭示为关键的坏死调节剂和缺血性心脏病的有希望的靶标。