Mitofusin 1 (MFN1)

Mitofusin-1 is a mediator of mitochondrial fusion. This protein and mitofusin 2 are homologs of the Drosophila protein fuzzy onion (Fzo). They are mitochondrial membrane proteins that interact with each other to facilitate mitochondrial targeting.

The deduced 741-amino acid protein contains an N-terminal GTPase domain and a transmembrane domain near the C terminus. MFN1 shares 60% identity with MFN2, with the most extensive homology in the GTPase domains. The N- and C-terminal ends are more variable. When stably expressed in COS-7 cells, MFN1 colocalized with mitochondrial markers. Overexpression of MFN1 caused perinuclear mitochondrial clustering.