Stromal interaction molecule 2 (STIM2)

Plays a role in mediating store-operated Ca(2+) entry (SOCE), a Ca(2+) influx after depletion of intracellular Ca(2+) stores. Functions as a highly sensitive Ca(2+) sensor in the endoplasmic reticulum which triggers both store-operated and store-independent Ca(2+)-influx.

Regulates basal cytosolic and endoplasmic reticulum Ca(2+) concentrations. Upon mild variations of the endoplasmic reticulum Ca(2+) concentration, translocates from the endoplasmic reticulum to the plasma membrane where it likely activates the Ca(2+) release-activated Ca(2+) (CRAC) channels ORAI1, ORAI2 and ORAI3.