Calcium Imaging of Store-Operated Calcium (Ca2+) Entry (SOCE) in HEK293 Cells Using Fura-2

  • Martin JohnsonEmail author
Part of the Methods in Molecular Biology book series (MIMB, volume 1925)


The store-operated calcium (Ca2+) entry (SOCE) pathway is an essential Ca2+ signaling pathway in non-excitable cells that serve many physiological functions. SOCE is mediated through the plasma membrane (PM) protein, Orai1, and the endoplasmic reticulum protein, stromal interaction molecule 1 (STIM1). One of the most well-established methods to study SOCE is using the Ca2+-sensing dye, fura-2. Here we describe a detailed protocol on how to use fura-2 to study Ca2+ signaling from SOCE in human embryonic kidney (HEK) cells.

Key words

Calcium imaging Fura-2 AM Store-operated calcium entry Orai1 STIM1 Thapsigargin 



I would like to thank Mohamed Trebak, Ryan Yoast, and Scott Emrich for critical reading of this manuscript. Research in the author’s laboratory is supported by grants from the NIH.


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© Springer Science+Business Media, LLC, part of Springer Nature 2019

Authors and Affiliations

  1. 1.Department of Cellular and Molecular PhysiologyThe Pennsylvania State University College of MedicineHersheyUSA

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