The TIMM8B 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.
Probable mitochondrial intermembrane chaperone that participates in the import and insertion of some multi-pass transmembrane proteins into the mitochondrial inner membrane. Also required for the transfer of beta-barrel precursors from the TOM complex to the sorting and assembly machinery (SAM complex) of the outer membrane. Acts as a chaperone-like protein that protects the hydrophobic precursors from aggregation and guide them through the mitochondrial intermembrane space (By similarity).