This family consists of several plant specific mitochondrial import receptor subunit TOM20 (translocase of outer membrane 20 kDa subunit) proteins. Most mitochondrial proteins are encoded by the nuclear genome, and are synthesised in the cytosol. TOM20 is a general import receptor that binds to mitochondrial pre-sequences in the early step of protein import into the mitochondria [1].

1: Peptide library approach with a disulfide tether to refine the Tom20 recognition motif in mitochondrial presequences. Obita T, Muto T, Endo T, Kohda D; J Mol Biol 2003;328:495-504. PMID:12691756