MCU (D2Z3B) Rabbit mAb #14997

The mitochondrial calcium uniporter (MCU) is an inner membrane transport protein that is essential for the regulation of calcium uptake and the maintenance of mitochondrial calcium homeostasis (1). MCU is responsible for the rapid transport of calcium ions across the inner membrane and into the mitochondrial matrix, taking advantage of the membrane potential generated by the electron transport chain. Subsequent release of calcium from the matrix through antiporter proteins regulates a number of biological processes, including signal transduction, bioenergetics, and cell death and survival (2,3). The MCU protein contains a pair of transmembrane domains with both carboxy- and amino-terminal ends within the mitochondrial matrix (3). The surrounding uniporter complex contains a number of proteins that regulate calcium ion transport, including the mitochondrial calcium uniporter regulator 1 (MCUR1), mitochondrial calcium uptake proteins 1 and 2 (MICU1, MICU2), and the essential MCU regulator EMRE (3). MICU1 stabilizes the closed state of the transport complex and preserves the normal mitochondrial calcium concentration below the equilibrium level during resting conditions (4). The MCUR1 protein is an essential regulator of calcium uptake, with decreased ion transport in cells with reduced MCUR1 expression (2). EMRE is also essential for MCU transport function where it functions as bridge between MCU uniporter activity and the calcium-sensing MICU1/2 proteins (5).