The Complex Dance of Organelles during Mitochondrial Division

Mitochondria are dynamic organelles that undergo cycles of fission and fusion events depending on cellular requirements. During mitochondrial division, the GTPase dynamin-related protein-1 is recruited to endoplasmic reticulum (ER)-induced mitochondrial constriction sites where it drives fission. However, the events required to complete scission of mitochondrial membranes are not well understood. Here, we emphasize the recently described roles for Golgi-derived phosphatidylinositol 4-phosphate (PI4P)-containing vesicles in the last steps of mitochondrial division. We then propose how trans-Golgi network vesicles at mitochondria-ER contact sites and PI4P generation could mechanistically execute mitochondrial division, by recruiting PI4P effectors and/or the actin nucleation machinery. Finally, we speculate on mechanisms to explain why such a complex dance of different organelles is required to facilitate the remodelling of mitochondrial membranes.

Automated summary

Mitochondria are dynamic organelles that can adapt to cellular needs through cycles of division and fusion events. Recent research has highlighted the important role of Golgi-derived PI4P-containing vesicles in the final steps of mitochondrial division, proposing a mechanism involving the recruitment of PI4P effectors and/or the actin nucleation machinery. Speculation on the necessity of a complex coordination of different organelles to facilitate mitochondrial membrane remodeling is also discussed.