Delineating the Function of TDP-43 in Skeletal Muscle Formation

描述 TDP-43 在骨骼肌形成中的功能

基本信息

批准号：
10158110
负责人：
Theodore Ewachiw
金额：
$ 3.81万
依托单位：
UNIVERSITY OF COLORADO
依托单位国家：
美国
项目类别：
财政年份：
2021
资助国家：
美国
起止时间：
2021-02-10 至 2024-01-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10158110
关键词：
Actins Address Aging Amyotrophic Lateral Sclerosis Binding Binding Sites Cell Differentiation process Cell Maturation Cell Nucleus Cells Chemicals Cre driver Cytoplasmic Granules Cytoplasmic Protein Data Degenerative Disorder Development Disease Growth In Vitro Inclusion Body Myositis Injury Knock-out Knockout Mice Knowledge Lead Learning Maintenance Messenger RNA Mitotic Mus Muscle Muscle Cells Muscle function Muscle satellite cell Myofibrillogenesis Natural regeneration Neuromuscular Diseases Oculopharyngeal Muscular Dystrophy Pathologic Pathology Patients Play Proteins RNA Binding RNA-Binding Proteins Role Sarcomeres Shapes Site Skeletal Muscle Stress Structural Protein Structure TDP-43 aggregation Transcript Ursidae Family Work connectin cytotoxic experimental study in vivo in vivo Model interest muscle regeneration neuromuscular particle prevent protein TDP-43 protein aggregation regenerative repaired skeletal disorder skeletal muscle differentiation skeletal regeneration stem cells

项目摘要

PROJECT ABSTRACT/SUMMARY Many degenerative neuromuscular diseases are associated with cytoplasmic accumulation of protein aggregates. These aggregates are widely considered to contribute disease and thus are thought to be toxic to the cell. Recently, we discovered similar aggregates, termed myo-granules, in healthy regenerating and differentiating skeletal muscle. Myo-granules contain RNA and RNA-binding proteins. One prominent RNA- binding protein found in myo-granules, TDP-43, is of particular interest due to its presence in aggregates observed in degenerative disease. Further, myo-granules localize to developing sarcomeres and contain an abundance of sarcomeric mRNAs that bear TDP-43 binding-sites. As the muscle regenerates and sarcomeres are replaced, myo-granules are cleared and TDP-43 re-localizes to the nuclei. Together, these findings suggest that TDP-43 may play a role in facilitating sarcomere formation and that accumulation of TDP-43 containing- aggregates found in disease may not be the cause but instead the result of recurring attempts at skeletal regeneration. In pre-liminary work, I found that TDP-43 deletion in muscle stem cells prevents differentiation, identifying an essential role for TDP-43 in skeletal muscle. Specific Aim 1 will evaluate the role of TDP-43 in myofiber formation and maturation during regeneration. To accomplish this, I will delete TDP-43 at regenerative checkpoints for fusion of differentiated cells and for maturation of the regenerating muscle. The results from aim 1 will be used to inform experiments in Specific Aim 2 where I will analyze the role of TDP- 43 in sarcomere formation. In pre-liminary work, TDP-43 deletion in differentiating cells during regeneration results in muscle that is improperly repaired and myofiber size is drastically reduced. Additionally, myofiber maturation is reduced when TDP-43 is deleted as indicated by the continued expression of developmental sarcomeric proteins. Thus, is TDP-43 required for sarcomere regeneration and repair? I will ask this question by taking an in vivo approach where TDP-43 will be deleted in both healthy and regenerating muscle to evaluate the effect on sarcomere formation, maturation, and degradation. Delineating the function of TDP-43 in sarcomere formation should lead to a better understanding of the relationship between myo-granules and disease-associated TDP-43 aggregates.

项目摘要/总结许多退行性神经肌肉疾病与蛋白质的细胞质积累有关聚合体。这些聚集体被广泛认为会导致疾病，因此被认为对人体有毒。细胞。最近，我们在健康的再生和健康中发现了类似的聚集体，称为肌颗粒。区分骨骼肌。肌颗粒含有 RNA 和 RNA 结合蛋白。一种著名的 RNA- 肌颗粒中发现的结合蛋白 TDP-43 由于其存在于聚集体中而受到特别关注在退行性疾病中观察到。此外，肌颗粒定位于发育中的肌节并含有大量带有 TDP-43 结合位点的肌节 mRNA。随着肌肉和肌节的再生被替换，肌颗粒被清除，TDP-43 重新定位到细胞核。总之，这些发现表明 TDP-43可能在促进肌节形成中发挥作用，并且TDP-43的积累含有- 疾病中发现的聚集体可能不是原因，而是骨骼反复尝试的结果再生。在前期工作中，我发现肌肉干细胞中TDP-43的缺失会阻止分化，确定 TDP-43 在骨骼肌中的重要作用。具体目标 1 将评估 TDP-43 在再生过程中肌纤维的形成和成熟。为了实现这一点，我将删除 TDP-43 用于分化细胞融合和再生肌肉成熟的再生检查点。这目标 1 的结果将用于为特定目标 2 中的实验提供信息，我将在其中分析 TDP-的作用 43位于肌节形成中。在前期工作中，再生过程中分化细胞中TDP-43的缺失导致肌肉修复不当，肌纤维尺寸急剧减小。此外，肌纤维当 TDP-43 被删除时，成熟度会降低，如发育性细胞的持续表达所表明的那样。肌节蛋白。那么，TDP-43 是肌节再生和修复所必需的吗？我会问这个问题通过采用体内方法，在健康和再生肌肉中删除 TDP-43 评估对肌节形成、成熟和降解的影响。描述 TDP-43 的功能肌节形成过程中的研究应该有助于更好地理解肌颗粒和肌节之间的关系疾病相关的 TDP-43 聚集体。