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Updated: Aug 9, 2026

Single-Cell Calcium Imaging for Studying the Activation of Calcium Ion Channels
07:17

Single-Cell Calcium Imaging for Studying the Activation of Calcium Ion Channels

Published on: December 13, 2024

Integrin receptor activation triggers converging regulation of Cav1.2 calcium channels by c-Src and protein kinase A

Peichun Gui1, Xin Wu, Shizhang Ling

  • 1Department of Medical Pharmacology & Physiology, University of Missouri School of Medicine, Columbia, Missouri 65212, USA.

The Journal of Biological Chemistry
|March 24, 2006
PubMed

Insights

Alpha5beta1 integrin activation acutely potentiates L-type calcium channels (CaL) in brain and muscle cells. This regulation involves specific phosphorylation sites on the alpha1C subunit, highlighting integrin-channel interactions in cellular function.

Area of Science:

  • Cellular Biology
  • Neuroscience
  • Cardiovascular Biology

Background:

  • L-type, voltage-gated calcium channels (CaL) are crucial for neuronal and muscle cell excitability.
  • Integrin-extracellular matrix (ECM) interactions are increasingly recognized for their role in cellular signaling.

Purpose of the Study:

  • To investigate the role of alpha5beta1 integrin activation in regulating CaL channel function.
  • To identify the specific molecular mechanisms underlying integrin-mediated CaL channel potentiation.

Main Methods:

  • Heterologous expression of neuronal and smooth muscle CaL channel isoforms.
  • Truncation and site-directed mutagenesis of the alpha1C subunit.
  • Kinase assays to assess phosphorylation.
  • Patch-clamp electrophysiology on native CaL channels in rat arteriolar smooth muscle.

Main Results:

  • Alpha5beta1 integrin activation acutely potentiates currents through neuronal and smooth muscle CaL channel isoforms.
  • The alpha1C pore-forming subunit is critical for this potentiation.
  • Phosphorylation of alpha1C C-terminal residues Ser1901 (by PKA) and Tyr2122 (by c-Src) is required for regulation.
  • Combined PKA and Src inhibition blocked CaL channel potentiation in native smooth muscle cells.

Conclusions:

  • Integrin-ECM interactions provide a common mechanism for acute regulation of CaL channels in both brain and muscle.
  • These findings underscore the significance of integrin-channel crosstalk in cellular responses to injury and the control of synaptic and vascular function.

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