Modulators of cardiomyocyte structure to promote functional recovery during cardiac regeneration and repair

心肌细胞结构调节剂促进心脏再生和修复过程中的功能恢复

• 批准号: 10751640
• 负责人: Brian A Link
• 金额: $ 53.05万
• 依托单位: MEDICAL COLLEGE OF WISCONSIN
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-07-17 至 2027-06-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10751640
• 关键词: Actins; Adult; Amputation; Automobile Driving; Binding Proteins; Cardiac; Cardiac Death; Cardiac Myocytes; Cell Culture Techniques; Cell Cycle; Cell Shape; Cells; Cellular Morphology; Cellular Structures; Cessation of life; Complex; Cues; Cytokinesis; Cytoskeletal Proteins; Cytoskeleton; Development; Disease; Embryo; Functional Regeneration; Genes; Genetic; Heart; Heart Injuries; Heart failure; Hypertrophy; Impairment; Injury; Intercalated disc; Intercellular Junctions; Ischemia; Lower Organism; Mammals; Mediating; Modeling; Morphogenesis; Mus; Muscle; Myocardial dysfunction; Myocardium; Natural regeneration; Neonatal; Nuclear; Pathway interactions; Patients; Phenotype; Phosphorylation; Phosphotransferases; Physiological; Proliferating; Proteins; Rationalization; Recovery of Function; Regenerative response; Regulation; Reporting; Role; Signal Pathway; Signal Transduction; Stress; Structural Protein; Structure; Testing; Therapeutic; Transgenic Mice; Zebrafish; cardiac regeneration; cardiac repair; cardiogenesis; falls; heart function; insight; interest; mouse model; mutant; myocardial injury; neonatal mice; novel; regenerative; regenerative approach; regenerative treatment; repaired; response; response to injury; transcription factor

PROJECT SUMMARY The governing premise of this application is that cardiac injury response falls along a continuum, depending on species, developmental stage, as well as therapeutic/experimental manipulation. Lower organisms such as zebrafish and neonatal mice are capable of complete heart regeneration following partial amputation or ischemic- induced cardiomyocyte (CM) death. Remuscularization is facilitated by proliferation of pre-existing cardiomyocytes (CMs). On the other hand, in response to cardiac injury or stress in adult mammals, CMs fail to proliferate and instead undergo adverse hypertrophic remodeling that can result in cardiac dysfunction. There is great interest in identifying molecules and signaling cues that guide CMs to undergo a proliferative versus hypertrophic response so that we can modulate these factors to promote adult mammalian cardiac regeneration and repair in response to injury. In this proposal we investigate the hypothesis that junctional and cytoarchitectural proteins are key effectors that regulate how CMs respond to injury. Modulation of these proteins coordinate the proliferative state of CMs, but also facilitate proper re-integration of CMs with neighboring cells during cardiac regeneration. In preliminary studies, we initiated a screen for cardiac development and regeneration in zebrafish mutants that disrupt factors known to regulate cell junctional and cytoskeletal proteins. The selected proteins have known interactions with Hippo-Yap signaling, a pathway of significant interest for promoting cardiac regeneration. From this screen, we identified Llgl1 as critical for zebrafish heart morphogenesis and development, and Shroom3 as a factor that is critical for regulation of CM proliferation during zebrafish heart regeneration. Subsequently, we found that CM specific deletion of either Llgl1 or Shroom3 impairs intercalated disc integrity which was associated with aberrant CM cell cycle activity in uninjured hearts. Here, we propose to delineate the cellular and physiological role of Llgl1 and Shroom3 in mammalian CMs during development and the post cardiac injury response in neonatal and adult mice, and to further investigate the mechanism by which these proteins interact with Hippo-Yap pathway components. Aims 1 and 2 employ transgenic mice with CM specific deletion of Llgl1 or Shroom3, respectively, to investigate the role of these two proteins in cardiac development and the post injury response with emphasis on cell morphology and establishment of junctional complexes and intercalated discs. We employ the zebrafish model to investigate the mechanisms underlying Llgl1 and Shroom3 functions, and whether these factors are co-regulated by the Hippo kinase, Lats1/2. Collectively, our proposed studies will elucidate the role of key effectors of the cardiac injury response, capable of modulating CM cytoarchitecture and cell-cell junctions to promote functional regeneration and restore a healthy myocardium.

项目概要 该应用的控制前提是心脏损伤反应沿着连续体下降，具体取决于 物种、发育阶段以及治疗/实验操作。低等生物如 斑马鱼和新生小鼠在部分截肢或缺血后能够完全再生心脏 诱导心肌细胞（CM）死亡。先前存在的增殖促进了再肌肉化 心肌细胞（CM）。另一方面，为了应对成年哺乳动物的心脏损伤或压力，CM 无法 增殖，反而会发生不利的肥厚重塑，从而导致心脏功能障碍。有 对识别引导 CM 进行增殖与增殖的分子和信号线索非常感兴趣 肥厚反应，以便我们可以调节这些因素以促进成年哺乳动物心脏再生 并针对损伤进行修复。在这个提案中，我们研究了连接和 细胞结构蛋白是调节 CM 如何响应损伤的关键效应子。这些蛋白质的调节 协调 CM 的增殖状态，同时也促进 CM 与邻近细胞的正确重新整合 在心脏再生过程中。在初步研究中，我们启动了心脏发育筛查 斑马鱼突变体的再生破坏已知调节细胞连接和细胞骨架蛋白的因子。 所选蛋白质与 Hippo-Yap 信号传导具有已知的相互作用，Hippo-Yap 信号传导是人们非常感兴趣的途径 促进心脏再生。从这个屏幕中，我们确定 Llgl1 对斑马鱼心脏至关重要 形态发生和发育，Shroom3 作为调节 CM 增殖的关键因子 斑马鱼心脏再生。随后，我们发现 CM 特异性删除了 Llgl1 或 Shroom3 损害闰盘完整性，这与未受伤心脏中异常的 CM 细胞周期活动有关。 在这里，我们建议描述 Llgl1 和 Shroom3 在哺乳动物 CM 过程中的细胞和生理作用。 新生和成年小鼠的发育和心脏损伤后反应，并进一步研究 这些蛋白质与 Hippo-Yap 通路成分相互作用的机制。目标 1 和 2 使用 分别具有 CM 特异性缺失 Llgl1 或 Shroom3 的转基因小鼠，以研究这两者的作用 心脏发育和损伤后反应中的蛋白质，重点是细胞形态和 建立连接复合体和闰盘。我们利用斑马鱼模型来研究 Llgl1 和 Shroom3 功能的机制，以及这些因素是否由 Hippo 共同调节 激酶，Lats1/2。总的来说，我们提出的研究将阐明心脏损伤关键效应物的作用 反应，能够调节 CM 细胞结构和细胞间连接以促进功能再生 并恢复健康的心肌。