ORAI1(redirected from calcium release-activated calcium channel protein 1)
ORAI1A gene on chromosome 12q24.31 that encodes a Ca2+ release-activated Ca2+ (CRAC) channel subunit, which mediates Ca2+ influx following depletion of intracellular Ca2+ stores and channel activation by the Ca2+ sensor, STIM1. CRAC channels are the main pathway for Ca2+ influx in T cells and promote an immune response to pathogens by activating the transcription factor NFAT.
Defects in ORAI1 cause immune dysfunction with T-cell inactivation due to calcium entry defect type 1.
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