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Whole-Cell Recording of Calcium Release-Activated Calcium (CRAC) Currents in Human T Lymphocytes
15:29

Whole-Cell Recording of Calcium Release-Activated Calcium (CRAC) Currents in Human T Lymphocytes

Published on: December 21, 2010

Calcium signaling in lymphocytes

Masatsugu Oh-hora1, Anjana Rao

  • 1Department of Pathology, Harvard Medical School, Immune Disease Institute, Boston, MA 02115, USA.

Current Opinion in Immunology
|June 3, 2008
PubMed

Insights

Calcium signals are vital for immune cell functions. This review details the STIM/ORAI and calcineurin/NFAT pathways regulating store-operated calcium entry via CRAC channels.

Area of Science:

  • Immunology
  • Cell Biology
  • Molecular Biology

Background:

  • Calcium signals are crucial for immune cell functions like differentiation and gene transcription.
  • Immunoreceptor engagement triggers intracellular calcium increases via store depletion and subsequent entry.
  • Store-operated calcium entry through CRAC channels is a major pathway for calcium increase in immune cells.

Purpose of the Study:

  • To review the signaling pathways upstream and downstream of calcium influx.
  • To highlight the roles of STIM and ORAI in regulating CRAC channel function.
  • To provide insights into the molecular mechanisms of calcium signaling in immune cells.

Main Methods:

  • Literature review of recent breakthroughs in CRAC channel research.
  • Focus on signaling pathways involving STIM, ORAI, calcineurin, and NFAT.
  • Analysis of the sequential operation of calcium store depletion and entry.

Main Results:

  • Identification of STIM and ORAI as key regulators of CRAC channels.
  • Elucidation of the STIM/ORAI pathway upstream of calcium influx.
  • Description of the calcineurin/NFAT pathway downstream of calcium influx.

Conclusions:

  • STIM and ORAI are essential for store-operated calcium entry in immune cells.
  • Understanding these pathways is critical for comprehending immune cell function.
  • This review consolidates current knowledge on CRAC channel regulation and downstream signaling.

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