Methods for studying store-operated calcium entry

Activation of surface membrane receptors coupled to phospholipase C results in the generation of cytoplasmic Ca(2+), signals comprised of both intracellular Ca(2+) release, and enhanced entry of Ca(2+) across the plasma membrane. A primary mechanism for this Ca(2+) entry process is attributed to store-operated Ca(2+) entry, a process that is activated by depletion of Ca(2+) ions from an intracellular store by inositol 1,4,5-trisphosphate. Our understanding of the mechanisms underlying both Ca(2+) release and store-operated Ca(2+) entry have evolved from experimental approaches that include the use of fluorescent Ca(2+) indicators and electrophysiological techniques. Pharmacological manipulation of this Ca(2+) signaling process has been somewhat limited; but recent identification of key molecular players, STIM and Orai family proteins, has provided new approaches. Here we describe practical methods involving fluorescent Ca(2+) indicators and electrophysiological approaches for dissecting the observed intracellular Ca(2+) signal to reveal characteristics of store-operated Ca(2+) entry. highlighting the advantages, and limitations, of these approaches. Published by Elsevier Inc.