MPC1 also known as BRP44L is part of an MPC1/MPC2 heterodimer that is responsible for transporting pyruvate into mitochondria. MPC1  a core component of the MPC complex that transports cytosolic pyruvate across the inner mitochondrial membrane to fuel the TCA cycle and oxidative phosphorylation. By regulating pyruvate entry, MPC1 influences glycolysis–mitochondria coupling, anaplerosis, and metabolic flexibility during nutrient stress and differentiation. Altered MPC1 activity has been linked to rewired cellular energetics observed in proliferative states and mitochondrial metabolic disorders, with downstream effects on redox balance and biosynthetic pathways.