Caspase-mediated nuclear pore complex trimming in myogenesis and muscular dystrophies

肌生成和肌营养不良中半胱天冬酶介导的核孔复合物修剪

• 批准号: 10591953
• 负责人: Ukrae Cho
• 金额: $ 12.57万
• 依托单位: SALK INSTITUTE FOR BIOLOGICAL STUDIES
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-02-01 至 2025-11-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10591953
• 关键词: Apoptosis; Apoptotic; Binding; Binding Proteins; Biological; Biology; Caspase; Cell Death; Cell Fractionation; Cell Nucleus; Cells; ChIP-seq; Chronic; Chronic Disease; Complex; Cytoplasm; Data; Deacetylase; Deterioration; Disease Progression; Dissociation; Distal; Duchenne muscular dystrophy; Equation; Focal Adhesions; Foundations; Genes; Genetic Transcription; Genome; Goals; Health; Homeostasis; Impairment; Individual; Life; Life Cycle Stages; Limb structure; Limb-Girdle Muscular Dystrophies; Mass Spectrum Analysis; Mediating; Membrane; Mentored Research Scientist Development Award; Muscle; Muscle Cells; Muscle Development; Muscle Fibers; Muscular Atrophy; Muscular Dystrophies; Myoblasts; Myopathy; Nuclear; Nuclear Export; Nuclear Pore Complex; Nucleosomes; Outcome; PTK2 gene; Pathologic; Pathway interactions; Patients; Peptide Hydrolases; Phenotype; Process; Protein Biosynthesis; Proteins; Proteome; Regulation; Regulation of Proteolysis; Research; Risk; Role; Sarcoplasmic Reticulum; Signal Transduction; Site; Skeletal Muscle; Stress; Structure; System; Time; Tubulin; ZYX gene; cofactor; coping; derepression; endoplasm; endoplasmic reticulum stress; fascinate; gene repression; genome-wide; invention; mRNA Export; mouse model; muscle stress; myogenesis; novel strategies; novel therapeutic intervention; nucleocytoplasmic transport; paxillin; pleiotropism; prevent; promoter; stressor; transcription factor; transcriptome sequencing

PROJECT SUMMARY/ABSTRACT Caspases are a group of proteases most well known for their destructive role in apoptosis. While their activation is often equated with cell death, in skeletal muscles, this does not hold true. For example, during myogenic differentiation, caspases are activated in a transient, regulated, and reversible manner. These proteases can also be activated chronically in Duchenne or limb-girdle muscular dystrophies. Nevertheless, very little is known about the non-apoptotic roles of caspases in muscle formation and degeneration. By focusing on caspase-mediated trimming of the nuclear pore complex (NPC), this K01 project will elucidate how sublethal caspases bring about such contrasting outcomes. Caspases can proteolyze four distal subunits of the NPC, impair nuclear export, and entrap several NES (nuclear export signal)-containing proteins, many of which have genome regulatory functions. In Aim 1, NES-containing proteins that accumulate in the nucleus during myogenesis and drive genome reconfiguration will be identified in an unbiased manner. In addition, a focused study will be conducted to understand how FAK, an NES-containing focal adhesion protein that doubles as a transcription cofactor in the nucleus, interacts with MBD2, a methyl CpG-binding protein, to de-repress myogenic genes. In Aim 2, caspase-mediated NPC trimming in dystrophic muscles will be assessed. Given that modest activation of caspases by ER stressors is sufficient to cause NPC trimming and nuclear export shutdown in myotubes, the NPC in dystrophic muscles will be similarly modified and dysfunctional. Therefore, a proteome- wide search will be performed to identify proteins whose nuclear levels are abnormally high in dystrophic myonuclei and have potential to induce genome dysregulation. In short, by dissecting the antagonistic pleiotropy of the caspase-NPC-nuclear export axis, this proposal aims to provide a foundation for new therapeutic approaches that promote muscular health in both healthy individuals and muscular dystrophy patients. This research combines the expertise of the Martin Hetzer lab (the Salk Institute) in the NPC and that of the Lorenzo Puri lab (Sanford-Burnham-Prebys) in muscle biology. Dr. Cho’s long-term goal is to lead a research group that studies nuclear proteome and proteases in the context of myogenesis and muscular dystrophies. K01 award will provide him the stability, networking opportunity, and confidence to develop into a young leader in the field of muscle biology who is proficient in both reductionist and systems approaches.

项目概要/摘要 半胱天冬酶是一组以其在细胞凋亡中的破坏性作用而闻名的蛋白酶。 激活通常等同于细胞死亡，但在骨骼肌中，这并不成立。 在肌原性分化过程中，半胱天冬酶以瞬时、可调节和可逆的方式被激活。 杜氏肌营养不良症或肢带型肌营养不良症中的蛋白酶也可能被长期激活。 关于半胱天冬酶在肌肉形成和退化中的非凋亡作用知之甚少。 半胱天冬酶介导的核孔复合物 (NPC) 修剪，这个 K01 项目将阐明亚致死性的机制 Caspases 可以蛋白水解 NPC 的四个远端亚基，从而产生这种截然不同的结果。 损害核输出，并捕获一些含有 NES（核输出信号）的蛋白质，其中许多具有 在目标 1 中，含有 NES 的蛋白质在细胞核中积累。 此外，将以公正的方式确定肌生成和驱动基因组重新配置。 将进行研究以了解 FAK（一种包含 NES 的粘着斑蛋白）如何兼作 细胞核中的转录辅助因子，与甲基 CpG 结合蛋白 MBD2 相互作用，以解除肌源性抑制 在目标 2 中，将评估营养不良性肌肉中 caspase 介导的 NPC 修剪。 ER 应激源激活半胱天冬酶足以导致 NPC 修剪和核输出关闭 肌管中，营养不良的肌肉中的 NPC 也会发生类似的改变并出现功能障碍。 将进行广泛的搜索，以确定营养不良中核水平异常高的蛋白质 肌核并有可能诱导基因组失调。 简而言之，通过剖析 caspase-NPC-核输出轴的拮抗多效性，该提案 旨在为促进肌肉健康的新治疗方法奠定基础 这项研究结合了 Martin Hetzer 实验室（the Martin Hetzer lab）的专业知识。 NPC 的索尔克研究所和 Lorenzo Puri 实验室（桑福德-伯纳姆-普雷比斯）的肌肉生物学博士。 Cho 的长期目标是领导一个研究小组，在以下背景下研究核蛋白质组和蛋白酶： K01 奖将为他提供稳定性、社交机会和机会。 有信心发展成为精通还原论和肌肉生物学领域的年轻领导者 系统方法。