Drp1 2026-10-20
A dynamin-related GTP-dependent protein recruited to mitochondrial constrictions during division.[ref]
The mitochondrial fission-fusion cycle is continuous remodeling of a mitochondrial population by division and merger. In mammalian biological cells, mitofusins promote fusion of outer mitochondrial membranes, while OPA1 supports fusion of inner mitochondrial membranes. Fusion mixes matrix contents and permits functional complementation between mitochondria. Genetic disruption and rescue of mitofusins demonstrated their requirement for normal mitochondrial fusion.[ref]
For fission, recruited Drp1 assembles at constrictions and uses GTP-dependent remodeling to help divide the organelle.[ref] The balance controls network shape, distribution and quality control. Division can help distribute mitochondria to daughter biological cells and segregate damaged portions for mitophagy; fusion can restore mixed contents. These are regulated competing events in a network, not an obligatory synchronized sequence that every mitochondrion completes on a fixed timetable.