Regulation of the actin filament pointed end dynamics in health and disease

健康和疾病中肌动蛋白丝尖端动态的调节

基本信息

批准号：
9310099
负责人：
Carol C Gregorio
金额：
$ 40.98万
依托单位：
WASHINGTON STATE UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2017
资助国家：
美国
起止时间：
2017-06-01 至 2021-05-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9310099
关键词：
Actins Affect Architecture Arizona Binding Binding Proteins Binding Sites Biological Assay Biophysics Cardiac Cardiac Myocytes Cardiomyopathies Cells Cellular biology Circular Dichroism Complex Consensus Contractile Proteins Data Development Developmental Biology Diagnostic Disease Equilibrium F-Actin Family Family member Genetic Goals Health Heart In Vitro Individual Induced Mutation Interdisciplinary Study Investigation Knockout Mice Laboratories Length Light Link Literature Maintenance Microfilaments Microscopy Minus End of the Actin Filament Modeling Molecular Molecular Biology Muscle Muscle Cells Muscle Contraction Muscle Fibers Muscle function Mutate Mutation Myofibrils Myopathy Nemaline Myopathies Nuclear Magnetic Resonance Pathogenesis Physiological Physiology Positioning Attribute Property Protein Isoforms Proteins Public Health Publishing Regulation Research Resolution Role Sarcomeres Skeletal Muscle Striated Muscles Structural Biochemistry Structure Testing Thin Filament Tropomyosin Universities Washington base biophysical properties cell type design experimental study genetic regulatory protein human disease improved in vivo member monomer mouse model muscular structure mutant new therapeutic target polymerization prevent protein complex protein structure structural biology three dimensional structure tropomodulin

项目摘要

Alterations in the thin filaments involved in cardiac/skeletal muscle contraction often produce cardiomyopathies/nemaline myopathies with fatal consequences. Our long-term goal is to identify the components and molecular mechanisms regulating actin architecture in muscle during normal development and disease. Our short-term goal is to determine the mechanisms of how thin filament lengths are regulated by the actin filament pointed end binding proteins, leiomodin (Lmod) and tropomoduin (Tmod). Polymerization at the pointed end determines thin filament length and is regulated directly by the binding of tropomodulin (Tmod) and leiomodin (Lmod). This binding is enhanced by the integral thin filament component, tropomyosin (Tpm). We hypothesize that maintenance of thin filament length requires the antagonistic action of Tmod and Lmod; that is, the role of Tmod is to prevent elongation at the pointed end while Lmod allows elongation. We also predict that Tmod and Lmod binding and action at the pointed end is determined by different arrangements of their Tpm- and actin-binding sites. To achieve our goals, a powerful, multidisciplinary collaboration has been established between the Kostyukova laboratory at Washington State University (with expertise in protein structure, structural biochemistry and biophysical properties of actin filaments and regulatory proteins) and the Gregorio laboratory at the University of Arizona (with expertise in the molecular, cellular and developmental biology of myofibril assembly). In this proposal we will combine a broad range of state-of-the-art approaches such as determination of high-resolution atomic structure of Lmod /Tpm binding interface, and use of advanced microscopy and physiological assessment of myocytes from Lmod2 or Lmod3 null mice to test our molecular designs. The proposed experiments will connect Lmod-related thin filament alterations with familial myopathies. A better understanding of thin filament function and of its regulation is critical to better understand muscle disease pathogenesis, to improve diagnostics and to potentially identify novel drug targets.

参与心肌/骨骼肌收缩的细丝的变化通常会产生具有致命后果的心肌病/线状肌病。我们的长期目标是确定正常发育过程中调节肌肉肌动蛋白结构的成分和分子机制和疾病。我们的短期目标是确定细丝长度如何调节的机制肌动蛋白丝尖端结合蛋白、leiomodin (Lmod) 和原调节蛋白 (Tmod)。聚合于尖端决定细丝长度，并由原调节蛋白 (Tmod) 的结合直接调节和leiomodin (Lmod)。这种结合通过完整的细丝成分原肌球蛋白 (Tpm) 得到增强。我们假设细丝长度的维持需要Tmod和Lmod的拮抗作用；也就是说，Tmod的作用是防止尖端伸长，而Lmod则允许伸长。我们也预测 Tmod 和 Lmod 在尖端的结合和作用是由不同的排列决定的它们的 Tpm 和肌动蛋白结合位点。为了实现我们的目标，我们进行了强有力的多学科合作与华盛顿州立大学 Kostyukova 实验室建立（拥有蛋白质领域的专业知识）肌动蛋白丝和调节蛋白的结构、结构生物化学和生物物理特性）以及亚利桑那大学格雷戈里奥实验室（拥有分子、细胞和发育方面的专业知识）肌原纤维组装的生物学）。在这个提案中，我们将结合广泛的最先进的方法例如确定 Lmod /Tpm 结合界面的高分辨率原子结构，以及使用先进的对 Lmod2 或 Lmod3 缺失小鼠的肌细胞进行显微镜检查和生理学评估，以测试我们的分子设计。拟议的实验将把 Lmod 相关的细丝改变与家族性联系起来。肌病。更好地了解细丝功能及其调节对于更好地理解细丝功能及其调节至关重要肌肉疾病的发病机制，以改善诊断并潜在地识别新的药物靶点。