Abstract：
Satellite cells, named for their satellite position around the sarcolemma of the myofibre, are responsible for skeletal muscle regeneration. Satellite cells normally reside in a quiescent state, but rapidly activate the myogenic program and the cell cycle in response to injury. Translational control of gene expression has emerged as an important regulator of satellite cell activity. Quiescent satellite cells maintain low levels of protein synthesis and selectively translate specific mRNAs to conserve limited energy. Activated satellite cells rapidly restore global protein synthesis to meet the demands of proliferating myogenic progenitors that participate in muscle repair. We propose a model by which translational control enables rapid protein level changes in response to injury-induced environmental shifts, serving as both a brake mechanism during quiescence and an accelerator for injury response. In this Chapter, we navigate the processing, translation and metabolism of newly transcribed mRNAs. We review the modifications of mRNA that occur during mRNA processing in the nucleus of satellite cells, and illustrate how these modifications impact the translation and stability of mRNAs. In the cytoplasm, we review how pathways work in concert to regulate protein synthesis globally, while trans acting microRNAs and RNA binding proteins modify specific mRNA translation within a context of tightly regulated protein synthesis. While navigating translational control of gene expression in satellite cells, this chapter reveals that despite significant progress, the field remains nascent in the broader scope of translational control in cell biology. We propose that future investigations will benefit from incorporating emerging global analyses to study translational control of gene expression in rare satellite cells, and we pose unanswered questions that warrant future exploration.
摘要：
卫星细胞,以它们在肌纤维肌膜周围的卫星位置命名，负责骨骼肌再生。卫星细胞通常处于静止状态，但迅速激活生肌程序和细胞周期以响应损伤。基因表达的翻译控制已成为卫星细胞活性的重要调节剂。静止的卫星细胞维持低水平的蛋白质合成并选择性地翻译特定的mRNA以保存有限的能量。活化的卫星细胞迅速恢复整体蛋白质合成以满足参与肌肉修复的增殖肌原祖细胞的需求。我们提出了一个模型，通过该模型，翻译控制可以使蛋白质水平快速变化以响应损伤引起的环境变化，既是静止时的制动机制，又是伤害反应的加速器。在这一章中,我们导航处理，新转录mRNA的翻译和代谢。我们回顾了在卫星细胞核中mRNA加工过程中发生的mRNA修饰，并说明这些修饰如何影响mRNA的翻译和稳定性。在细胞质中，我们回顾了通路如何协同工作来调节全球蛋白质合成，而反式作用的microRNA和RNA结合蛋白在严格调节的蛋白质合成的背景下修饰特定的mRNA翻译。在导航卫星细胞中基因表达的翻译控制时，本章揭示了尽管取得了重大进展，该领域在细胞生物学翻译控制的更广泛范围内仍处于起步阶段。我们建议，未来的研究将受益于纳入新兴的全球分析，以研究稀有卫星细胞中基因表达的翻译控制。我们提出了悬而未决的问题，值得未来的探索。
