ORAI Calcium Release Activated Calcium Modulator 2 (ORAI2)

By database analysis, Feske et al. (2006) identified human ORAI1, ORAI2, and ORAI3 as homologs of a Drosophila gene, Orai, that they identified through an RNA interference screen for regulators of store-operated calcium entry and nuclear factor of activated T cells (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).

Mercer et al. (2006) showed that coexpression of STIM1 with ORAI2 augmented store-operated Ca(2+) entry to a lesser extent than coexpression of STIM1 with ORAI1. Expression of ORAI2 or ORAI1 in the absence of STIM1 inhibited Ca(2+) entry.Feske et al. (2006) stated that the ORAI2 gene maps to chromosome 7.