Plays a role in mediating store-operated Ca(2+) entry (SOCE), a Ca(2+) influx following depletion of intracellular Ca(2+) stores. Acts as Ca(2+) sensor which upon Ca(2+) depletion, activates the Ca(2+) release-activated Ca(2+) (CRAC) channel subunit, orai-1. Essential for Ca (2+) and IP3-dependent contractile activity of gonad sheath cells and spermatheca. Essential for fertility. Does not play a role in posterior body wall muscle contraction (pBoc) rhythmicity, intestinal cell oscillatory Ca(2+) signaling or intestinal ER Ca(2+) hemostasis. Homodimer. Interacts with orai-1. Localizes to intracellular puncta in the anterior intestine and reticular structure in the posterior intestine. Coexpressed with orai-1 in spermatheca, gonad sheath cells and intestine. Also detected in neurons in the head and in the uterine epithelial cells. Heterogeneously expressed in the intestine with strong presence in the anterior and posterior intestine and weaker in the midsection. Sterility due to dysfunction of somatic cells. Affects the store-operated Ca(2+) (SOC) activity.