Measurement of Intracellular Ca2+ Concentration in Single Cells Using Ratiometric Calcium Dyes

  • Sonal Srikanth
  • Yousang GwackEmail author
Part of the Methods in Molecular Biology book series (MIMB, volume 963)


Measurement of intracellular Ca2+ concentration ([Ca2+]i) is useful to study the upstream and downstream events of Ca2+ signaling. Ca2+-binding proteins including EF-hand-containing proteins are important downstream effector molecules after an increase of [Ca2+]i. Conversely, these proteins can also act as key modulators for regulation of [Ca2+]i by sensing the Ca2+ levels in the intracellular organelles and cytoplasm. Here we describe a single-cell Ca2+ imaging technique that was used to measure the intracellular Ca2+ levels to examine the function of Ca2+-binding proteins, STIM1 and Calcium release-activated Calcium channel regulator 2A (CRACR2A), using ratiometric Ca2+ dye Fura-2 in adherent and non-adherent cells.

Key words

Store-operated Ca2+ entry Calcium release-activated Calcium (CRAC) channel Nuclear factor of activated T cells (NFAT) Ratiometric Ca2+ measurements Fura-2 Intracellular Ca2+ concentration EF-hand-containing proteins STIM1 Orai1 CRAC channel regulator (CRACR) 2A 



This work was supported by the National Institute of Health grants AI-083432 and AI-088393 to YG.


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Copyright information

© Springer Science+Business Media New York 2013

Authors and Affiliations

  1. 1.Department of PhysiologyDavid Geffen School of Medicine at UCLALos AngelesUSA

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