Mitochondrial intermembrane chaperone that participates in the import and insertion of multi-pass transmembrane proteins into the mitochondrial inner membrane. May also be 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.
Heterohexamer; composed of 3 copies of TIMM9 and 3 copies of TIMM10/TIM10A, named soluble 70 kDa complex. The complex forms a 6-bladed alpha-propeller structure and associates with the TIMM22 component of the TIM22 complex. Interacts with multi-pass transmembrane proteins in transit. Also forms a complex composed of TIMM9, TIMM10/TIM10A and FXC1/TIM10B.