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Updated: Jul 4, 2026

Identification of Inositol Phosphate or Phosphoinositide Interacting Proteins by Affinity Chromatography Coupled to Western Blot or Mass Spectrometry
08:07

Identification of Inositol Phosphate or Phosphoinositide Interacting Proteins by Affinity Chromatography Coupled to Western Blot or Mass Spectrometry

Published on: July 26, 2019

TRPM7 ion channels are required for sustained phosphoinositide 3-kinase signaling in lymphocytes

Jaya Sahni1, Andrew M Scharenberg

  • 1Department of Pediatrics, University of Washington and Seattle Children's Hospital Research Institute, Seattle, WA 98101, USA.

Cell Metabolism
|July 2, 2008
PubMed

Insights

Lymphocytes lacking TRPM7 channels cannot grow without sufficient extracellular Mg2+. TRPM7 is essential for sustained phosphoinositide 3-kinase signaling, regulating lymphocyte proliferation.

Area of Science:

  • Cell Biology
  • Ion Channel Physiology
  • Molecular Signaling

Background:

  • Lymphocytes require specific ion concentrations for proliferation.
  • TRPM7 (transient receptor potential cation channel, subfamily M, member 7) is a dual ion channel and protein kinase.
  • TRPM7-deficient lymphocytes show impaired proliferation in standard media but recover with Mg2+ supplementation.

Purpose of the Study:

  • To elucidate the molecular mechanisms behind the unique proliferation phenotype of TRPM7-deficient lymphocytes.
  • To investigate the role of TRPM7 in regulating lymphocyte growth and proliferation signaling pathways.

Main Methods:

  • Analysis of TRPM7-deficient lymphocytes transitioning between Mg2+-supplemented and regular media.
  • Assessment of cell growth rates and proliferation.
  • Investigation of phosphoinositide 3-kinase (PI3K) signaling pathways downstream of TRPM7.

Main Results:

  • TRPM7-deficient cells downregulate growth and arrest proliferation when Mg2+ is removed.
  • This growth arrest correlates with PI3K signaling deactivation.
  • Expressing constitutively active PI3K rescues growth and proliferation in regular media.

Conclusions:

  • TRPM7 channels are crucial for maintaining sustained PI3K-dependent growth signaling in lymphocytes.
  • TRPM7 acts as a central regulator of lymphocyte growth and proliferation, alongside PI3K.
  • TRPM7's function is vital for lymphocyte homeostasis, particularly under varying extracellular Mg2+ conditions.

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