This gene encodes a member of the evolutionarily conserved TIMM (translocase of inner mitochondrial membrane) family of proteins that function as chaperones in the import of proteins from the cytoplasm into the mitochondrial inner membrane. Proteins of this family play a role in collecting substrate proteins from the translocase of the outer mitochondrial membrane (TOM) complex and delivering them to either the sorting and assembly machinery in the outer mitochondrial membrane (SAM) complex or the TIMM22 complex in the inner mitochondrial membrane. The encoded protein and the translocase of mitochondrial inner membrane 8a protein form a 70 kDa complex in the intermembrane space. [provided by RefSeq, Jul 2013]