Ca(2+) release-activated Ca(2+) (CRAC) channel subunit which mediates Ca(2+) influx following depletion of intracellular Ca(2+) stores. Regulates transcription factor NFAT nuclear import. In Greek mythology, the 'Orai' are the keepers of the gates of heaven: Eunomia (order or harmony), Dike (justice) and Eirene (peace). Belongs to the Orai family.