This gene encodes a member of a well-conserved family of proteins with similarity to yeast Tim mitochondrial import proteins. This gene is encoded by a nuclear gene and is transported into the intermembrane space of the mitochondrion. When formed into complexes, these proteins guide membrane-spanning proteins across the mitochondrial intermembrane space before they are added into the mitochondrial inner membrane. This gene is adjacent to succinate dehydrogenase, subunit D (SDHD), in which mutations have been found in affected members of families with hereditary paraganglioma.[provided by RefSeq, Aug 2009]