PDF(Pubmed)
Abstract：
Changes in protein turnover play an important role in dynamic physiological processes, including skeletal muscle regeneration, which occurs as an essential part of tissue repair after injury. The inability of muscle tissue to recapitulate this regenerative process can lead to the manifestation of clinical symptoms in various musculoskeletal diseases, including muscular dystrophies and pathological atrophy. Here, we employed a workflow that couples deuterated water (2H2O) administration with mass spectrometry (MS) to systematically measure in-vivo protein turnover rates across the muscle proteome in 8-week-old male C57BL6/J mice. We compared the turnover kinetics of over 100 proteins in response to cardiotoxin (CTX) induced muscle damage and regeneration at unique sequential stages along the regeneration timeline. This analysis is compared to gene expression data from mRNA-sequencing (mRNA-seq) from the same tissue. The data reveals quantitative protein flux signatures in response to necrotic damage, in addition to sequential differences in cell proliferation, energy metabolism, and contractile gene expression. Interestingly, the mRNA changes correlated poorly with changes in protein synthesis rates, consistent with post-transcriptional control mechanisms. In summary, the experiments described here reveal the signatures and timing of protein flux changes during skeletal muscle regeneration, as well as the inability of mRNA expression measurements to reveal changes in directly measured protein turnover rates. The results of this work described here provide a better understanding of the muscle regeneration process and could help to identify potential biomarkers or therapeutic targets.
摘要：
蛋白质周转的变化在动态生理过程中起着重要作用,包括骨骼肌再生,这是损伤后组织修复的重要组成部分。肌肉组织无法概括这种再生过程可导致各种肌肉骨骼疾病的临床症状的表现，包括肌营养不良和病理性萎缩。这里,我们采用了将氘代水(2H2O)给药与质谱(MS)联用的工作流程,以系统地测量8周龄雄性C57BL6/J小鼠肌肉蛋白质组的体内蛋白质转换率.我们比较了超过100种蛋白质响应于心脏毒素（CTX）诱导的肌肉损伤和再生的周转动力学，以及沿着再生时间表的独特顺序阶段。将该分析与来自相同组织的mRNA测序(mRNA-seq)的基因表达数据进行比较。数据揭示了响应坏死损伤的定量蛋白质通量特征，除了细胞增殖的顺序差异外，能量代谢，和收缩基因表达。有趣的是,mRNA的变化与蛋白质合成率的变化相关性较差，与转录后控制机制一致。总之,这里描述的实验揭示了骨骼肌再生过程中蛋白质通量变化的特征和时间，以及mRNA表达测量无法揭示直接测量的蛋白质转换率的变化。本文描述的这项工作的结果提供了对肌肉再生过程的更好理解，并且可以帮助识别潜在的生物标志物或治疗靶标。
