FTMT (ferritin mitochondrial) is a mitochondrial iron-storage protein that catalyzes oxidation of ferrous iron (Fe²⁺) to ferric iron (Fe³⁺) and maintains intracellular iron homeostasis 1. Unlike cytosolic ferritin, FTMT has distinct regulatory mechanisms and is differentially expressed across tissues, with particularly high levels in brain and testis 2. FTMT protects cells from ferroptosis-mediated death by preventing mitochondrial iron overload and lipid peroxidation 34. Under hypoxia, FTMT expression increases through NCOA4-dependent mechanisms, protecting macrophages from ferroptotic cell death 5. Clinically, FTMT upregulation is neuroprotective in cerebral ischemia/reperfusion injury and germinal matrix hemorrhage by maintaining iron homeostasis and reducing oxidative stress 46. FTMT overexpression also protects against neurodegenerative diseases including Alzheimer's disease, Parkinson's disease, and Friedreich's ataxia 2. However, FTMT promotes glioma tumorigenesis and angiogenesis through the SNHG1/miR-9-5p regulatory axis, suggesting context-dependent roles in disease 7. These findings establish FTMT as a critical regulator of mitochondrial iron homeostasis with both protective and pathogenic functions depending on cellular context.