Mitochondrial import inner membrane translocase subunit TIM50 is an enzyme that in humans is encoded by the TIMM50 gene. Tim50 is a subunit of the Tim23 translocase complex in the inner mitochondrial membrane. Mutations in TIMM50 can lead to epilepsy, severe intellectual disability, and 3-methylglutaconic aciduria. TIMM50 expression is increased in breast cancer cells and decreased in hypertrophic hearts. The TIMM50 gene is located on the q arm of chromosome 19 in position 13.2 and spans 13,373 base pairs. The gene produces a 39.6 kDa protein composed of 353 amino acids. This gene encodes a subunit of the TIM23 inner mitochondrial membrane translocase complex, which mediates the translocation of transit peptide-containing proteins across the mitochondrial inner membrane. The Tim50 protein functions as the receptor subunit that recognizes the mitochondrial targeting signal, or presequence, on protein cargo that is destined for the mitochondrial inner membrane and matrix. This gene in human cells results in the release of cytochrome c and apoptosis. This protein plays a role in maintaining the membrane permeability barrier. The intermembrane space domain of Tim50 induces the translocation pore of the TIM23 channel to close.