Declining mitochondrial function and homeostasis is a hallmark of aging. It is appreciated that the role of mitochondria is much more complex than generating reactive oxygen species to cause aging-related tissue damage. More recent literature describes that the ability of mitochondria to undergo fission or fusion events with each other impacts aging processes. A dynamic balance of mitochondrial fission and fusion events is required to sustain critical cellular functions including cell cycle. Specifically, cell cycle regulators modulate molecular activities of the mitochondrial fission (and fusion) machinery towards regulating cell cycle progression. In this review, we discus literature leading to our understanding on how shifts in the dynamic balance of mitochondrial fission and fusion can modulate progression through, exit from, and re-entry to the cell cycle or in undergoing senescence. Importantly, core regulators of mitochondrial fission or fusion are emerging as crucial stem cell regulators. We discuss the implication of such regulation in stem cells in the context of aging, given that aberrations in adult stem cells promote aging. We also propose a few hypotheses that may provide direction for further understanding about the roles of mitochondrial fission-fusion dynamics in aging biology.

中文翻译：

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线粒体裂变融合与细胞周期调节的相互作用：对干细胞和机体衰老的可能影响。

线粒体功能和稳态下降是衰老的标志。可以理解，线粒体的作用比产生活性氧引起与衰老相关的组织损伤要复杂得多。最近的文献描述了线粒体彼此发生裂变或融合事件的能力会影响衰老过程。需要线粒体裂变和融合事件的动态平衡来维持包括细胞周期在内的关键细胞功能。具体而言，细胞周期调节剂调节线粒体裂变（和融合）机制的分子活动以调节细胞周期进程。在这篇综述中，我们讨论了有助于我们理解线粒体裂变和融合动态平衡的变化如何调节进展的文献，通过，退出，并重新进入细胞周期或经历衰老。重要的是，线粒体裂变或融合的核心监管机构正在成为关键的干细胞监管机构。考虑到成体干细胞的畸变会促进衰老，我们讨论了在衰老背景下干细胞中这种调节的意义。我们还提出了一些假设，这些假设可能为进一步了解线粒体裂变-融合动力学在衰老生物学中的作用提供指导。