Essential component of the PAM complex, a complex required for the translocation of transit peptide-containing proteins from the inner membrane into the mitochondrial matrix in an ATP-dependent manner. Seems to control the nucleotide-dependent binding of mitochondrial HSP70 to substrate proteins (By similarity). Probable component of the PAM complex at least composed of a mitochondrial HSP70 protein, Roe1, TIM44, blp/TIM16 and TIM14. Belongs to the GrpE family.