Alpha-Catenins in Mechanochemical Signaling

机械化学信号传导中的α-连环蛋白

• 批准号: 9130377
• 负责人: GLENN Lawrence RADICE
• 金额: $ 43.13万
• 依托单位: THOMAS JEFFERSON UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-09-01 至 2017-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9130377
• 关键词: Actins; Adherens Junction; Animal Model; Atomic Force Microscopy; Attention; Binding; Biomechanics; Birth; Cadherin Domain; Cadherins; Cardiac; Cardiac Myocytes; Cardiac development; Cell Cycle; Cell Nucleus; Cells; Couples; Cytokinesis; Cytoskeletal Modeling; Cytoskeletal Proteins; Cytoskeleton; Echocardiography; Elasticity; Engineering; Exhibits; Felis catus; Generations; Genes; Genetic; Goals; Guanine Nucleotide Exchange Factors; Health; Heart; Heart failure; Homeostasis; Hydrogels; Infarction; Intercalated disc; Knock-out; Knockout Mice; Measures; Mechanics; Mediating; Membrane; Microtubules; Molecular; Mus; Muscle Cells; Myocardial Infarction; Myocardial Ischemia; Myofibrils; N-Cadherin; Nuclear; Pathway interactions; Patients; Phenotype; Phosphotransferases; Physiological; Process; Proteins; Research; Role; Signal Pathway; Signal Transduction; Stimulus; Stress; Structure; System; Tissues; Transcription Coactivator; Tubulin; Withdrawal; alpha catenin; alphaT catenin; base; cardiac regeneration; cardiac repair; cell behavior; clinical application; extracellular; heart function; improved; improved functioning; inhibitor/antagonist; injured; novel; postnatal; premature; rapid growth; response; rho; rho GTP-Binding Proteins

DESCRIPTION (provided by applicant): In the early postnatal period, cardiomyocytes undergo rapid growth and maturation that is essential for normal cardiac development. Coincident with cardiomyocyte differentiation and cell cycle withdrawal is the establishment of the N-cadherin-based adherens junction (AJ), a critical determinant of intercalated disc (ID) structure that provides the end-to-end connection between cardiomyocytes. AJ are stabilized at the ID by the dynamic I has binding of the intracellular cadherin domain to the actin cytoskeleton via beta- and alpha-catenins. To explore the role of mechanotransduction in cardiac development and homeostasis, we developed a novel animal model (alpha-cat double knockout (DKO)) in which both cytoskeletal linker proteins alphaE- and alphaT-catenin were depleted in the heart. We discovered that alpha-catenin proteins normally inhibit the ability of postnatal cardiomyocytes to re-enter the cell cycle. A significant increase in nuclear Yap, a key component of the Hippo pathway, accompanied the increased proliferation in the alpha-cat DKO hearts. Importantly, we found that alpha-cat DKO mice exhibit improved cardiac function following myocardial infarction compared to their control littermates. We hypothesize that loss of �/�catenin causes cytoskeletal rearrangement and loss of tensional stress resulting in translocation of Yap to the nucleus where it activates genes critical for cardiomyocyte proliferation. The following interrelated aims are proposed: (1) To determine the cytoskeletal-based signaling pathways that regulate the cellular activity of Yap. (2) To define the functional relationship between N-cadherin/alpha- catenin/cytoskeleton interactions and myocyte elasticity and proliferation. Deformable N-cadherin- coated hydrogels will be used to determine how stiffness and N-cadherin/catenin-mediated cytoskeletal organization cooperate to regulate proliferation. Atomic force microscopy (AFM) will be used to measure cell and tissue stiffness in alpha-cat DKO under different physiological and pathological conditions. (3) In order to pursue clinical application, we will determine the window of opportunity for manipulating alpha-catenin/Yap pathway after myocardial infarction. The long term goal of this research is to determine if interfering with the cytoskeletal proteins, alpha-catenins, represents a potential therapy to enhance cardiac repair in heart failure patients.

描述（由申请人提供）：在出生后早期，心肌细胞经历快速生长和成熟，这对于正常心脏发育至关重要，与心肌细胞分化和细胞周期退出同时发生的是基于 N-钙粘蛋白的粘附连接 (AJ) 的建立。是闰盘 (ID) 结构的关键决定因素，它提供心肌细胞之间的端到端连接，通过动态 I 与细胞内钙粘蛋白的结合而稳定在 ID 处。为了探索机械转导在心脏发育和稳态中的作用，我们开发了一种新型动物模型（α-cat 双敲除（DKO）），其中细胞骨架连接蛋白 αE- 和我们发现，α-连环蛋白通常会抑制出生后心肌细胞重新进入细胞周期的能力。重要的是，我们发现与对照同窝小鼠相比，α-cat DKO 小鼠在心肌梗死后表现出更好的心脏功能。连环蛋白引起细胞骨架重排和张力应力丧失，导致 Yap 易位到细胞核，在细胞核中激活对心肌细胞增殖至关重要的基因。提出了以下相互关联的目标：（1）确定调节 Yap 细胞活性的基于细胞骨架的信号通路 (2) 定义 N-钙粘蛋白/α-连环蛋白/细胞骨架相互作用与肌细胞弹性和增殖之间的功能关系，将用于确定可变形的 N-钙粘蛋白涂层水凝胶。硬度和 N-钙粘蛋白/连环蛋白介导的细胞骨架组织如何配合调节增殖。原子力显微镜 (AFM) 将用于测量细胞和组织的硬度。 (3)为了追求临床应用，我们将确定心肌梗死后操纵α-catenin/Yap通路的机会窗口。本研究的长期目标是确定。如果干扰细胞骨架蛋白α-连环蛋白，则代表一种增强心力衰竭患者心脏修复的潜在疗法。