PYR + H+ (cytosol) => PYR + H+ (mitochondrial matrix) Authored: D'Eustachio, P, 2008-06-20 15:07:05 Cytosolic PYR is transported to the mitochondrial matrix by MPC1:MPC2 Edited: D'Eustachio, P, 2008-09-12 21:47:19 Pubmed11945601 Pubmed22628558 Pubmed4822737 Pyruvate (PYR) and a proton are transported from the cytosol into the mitochondrial matrix, mediated by a complex of MCP1 and MCP2 in the inner mitochondrial membrane. Studies of pyruvate uptake in rat indicate that it is specific, saturable, and competitively inhibitable, indicating a specific role for a membrane transport protein (Papa et al. 1971; Halestrap and Denton 1974), and the stoichiometry of the human reaction is inferred from this work. MCP1 and MCP2 have been identified as essential components of the transporter based on the observation that expression of both proteins (but not either one alone) restored mitochondrial pyruvate uptake in mutant budding yeast. The proteins form a multimeric complex; its stoichiometry is unknown (Bricker et al. 2012). Reactome Database ID Release 43372342 Reactome, http://www.reactome.org ReactomeREACT_14833 Reviewed: Harris, RA, 2008-09-10 18:47:12 Reviewed: Jassal, B, 2012-10-12