Translocase Of Outer Mitochondrial Membrane 20 (TOMM20)

The protein import machinery of the mitochondrial outer membrane is comprised of a dynamic complex of proteins that mediates translocation of cytosolic precursor proteins into or across the membrane. Several proteins within this complex have been identified, such as Mas20p in yeast and MOM19 in Neurospora crassa .

The 145-amino acid human polypeptide shares high similarity with Mas20p and MOM19 within the N-terminal region, but exhibits only weak homology to the tetratricopeptide-repeat B domain that is found in the other 2 proteins. The authors showed that human Mas20p is targeted and inserted into the outer membrane of isolated rat heart mitochondria in the N(in)-to-C(cyto) orientation.