Mitochondria shed their outer membrane in response to infection-induced stress

Mitochondria shed their SPOTs Outer mitochondrial membrane (OMM) function is essential for cellular health. How mitochondria respond to naturally occurring OMM stress is unknown. Li et al . show that, upon infection with the human parasite Toxoplasma gondii , mitochondria shed large structures positive for OMM (SPOTs). SPOT formation required the parasite effector TgMAF1 and its interaction with the host mitochondrial receptor TOM70 and translocase SAM50. TOM70-dependent SPOT formation mediated a depletion of mitochondrial proteins and optimal parasite growth. SPOT-like structures also formed after OMM perturbations independently of infection. Thus, membrane remodeling is a feature of cellular responses to OMM stress that Toxoplasma hijacks during infection. —SMH