Longevity & AgingScientists Crack How Cells Detect Damaged Mitochondria Before Parkinson's Develops
Researchers at NIH used a novel MFN2-Halo reporter and genome-wide CRISPRi screens to investigate how cells recognize damaged mitochondria. The PINK1-Parkin pathway, linked to recessive Parkinson's disease, normally clears damaged mitochondria via mitophagy. The study found that diverse forms of mitochondrial damage—including protein misfolding—all converge on loss of mitochondrial membrane potential (MMP) to stall PINK1 import. This stalling occurs specifically during PINK1's transfer from the outer membrane translocase TOM to the inner membrane translocase TIM23. Without MMP or TIM23, PINK1 accumulates on the mitochondrial surface, activates Parkin, and triggers mitophagy. Cellular energy status outside mitochondria further modulates the pathway by controlling new PINK1 synthesis.
