Plays a role in mitochondrial biogenesis and protein folding. Participates in the translocation of transit peptide-containing proteins from the inner membrane into the mitochondrial matrix in an ATP-dependent manner, probably by stimulating activity of mtHSP70 (SSC1). Interacts with PAM16/TIM16 and is recruited by the PAM complex. Present with 573 molecules/cell in log phase SD medium.