Opa1 is a dynamin-like guanosine triphosphatase required for mitochondrial fusion and regulation of apoptosis. Its activity is controlled by proteolytic cleavage. Stress conditions that cause loss of mitochondrial membrane potential can induce the cleavage of Opa1 at S1 position by OMA1 (an ATP-independent peptidase), and this triggers mitochondrial fragmentation []. It is also involved in mitochondrial cristae remodeling during apoptosis [].
