Mitochondrial Dynamics and Metabolic Regulation

Mitochondrial morphology varies tremendously across cell types and tissues, changing rapidly in response to external insults and metabolic cues, such as nutrient status. The many functions of mitochondria have been intimately linked to their morphology, which is shaped by ongoing events of fusion and fission of outer and inner membranes (OM and IM). Unopposed fission causes mitochondrial fragmentation, which is generally associated with metabolic dysfunction and disease. Unopposed fusion results in a hyperfused network and serves to counteract metabolic insults, preserve cellular integrity, and protect against autophagy. Here, we review the ways in which metabolic alterations convey changes in mitochondrial morphology and how disruption of mitochondrial morphology impacts cellular and organismal metabolism.

TrendsMitochondrial morphology varies widely across different cell types and tissues and results from the opposing and coordinated forces of mitochondrial fission and fusion of OMs and IMs.The regulation of fusion and fission is manifold and responds rapidly to metabolic cues.The fusion and fission machinery is essential for life, and genetic ablation of individual components in adult tissues impairs organ function and whole-body metabolism.Interpreting the relevance of mitochondrial morphology is complicated by the functional redundancy and additional roles that these components have within as well as outside mitochondria.