EFCAB4B Antibody

EFCAB4B, also known as Calcium release-activated calcium channel regulator 2A, is a novel Ca2+-binding EF-hand protein that is thought to play a key role in store-operated Ca2+ entry in T-cells by regulating CRAC channel activation. EFCAB4B acts as a cytoplasmic calcium-sensor that forms a complex with ORAI1 and STIM1 at the junctional regions between the plasma membrane and the endoplasmic reticulum upon low Ca2+ concentration. A closely related protein, EFCAB4A, is likely to play a similar role as EFCAB4B, but the detailed function of EFCAB4A is still under investigation.