cytochrome-c-t and Friedreich-Ataxia

Frataxin is a mitochondrial protein involved in iron metabolism. Defective expression of frataxin causes Friedreich ataxia (FA), an inherited degenerative syndrome characterized by ataxia, cardiomyopathy, and high incidence of diabetes. Here we report that frataxin-deficient cells are more prone to undergo stress-induced mitochondrial damage and apoptosis, while the overexpression of frataxin confers protection to a variety of cell types. Moreover, we reveal the existence of an extramitochondrial pool of frataxin, which can efficiently prevent mitochondrial damage and apoptosis in different cellular systems. Remarkably, extramitochondrial frataxin can fully replace mitochondrial frataxin in promoting survival of FA cells.

Topics: Antioxidants; Apoptosis; Cell Line; Cell Line, Tumor; Cell Survival; Cytochromes c; Frataxin; Friedreich Ataxia; HeLa Cells; Humans; Iron-Binding Proteins; Jurkat Cells; Mitochondria; Oxidative Stress; Reactive Oxygen Species