Mitochondrial and ER contact sites related to physiology and diseases

Mitochondria and the endoplasmic reticulum (ER) are indispensable organelles in eukaryotic cells, playing pivotal roles in energy production, calcium homeostasis, and lipid synthesis. The specialized contact sites between these two organelles, known as mitochondria-associated ER membranes (MERCs), facilitate fundamental cellular functions such as lipid metabolism, and apoptosis. Disruption of MERCs is implicated in various diseases, including neurodegenerative disorders, cardiovascular diseases, diabetes. This review delves into the dynamics of mitochondria, the importance of MERCs, and their implications in disease pathogenesis. We have explored the processes of mitochondrial fusion and fission, regulated by proteins such as mitofusins and dynamin-related protein 1, and their impact on mitochondrial quality control and cellular stress responses. Furthermore, we investigate the role of the ER in mitochondrial dynamics, with a focus on how ER-mitochondria interactions influence cellular homeostasis. By unraveling the complex mechanisms governing MERCs, we can identify potential therapeutic targets for diseases associated with MERC dysfunction, thereby offering new avenues for treatment.