Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Review
. 2003 May-Jun;33(5-6):311-21.
doi: 10.1016/s0143-4160(03)00045-9.

CRAC channels: activation, permeation, and the search for a molecular identity

Murali Prakriya  1 , Richard S Lewis
Affiliations
Review

CRAC channels: activation, permeation, and the search for a molecular identity

Murali Prakriya et al. Cell Calcium. 2003 May-Jun.

Abstract

The Ca2+ release-activated Ca2+ (CRAC) channel is a highly Ca2+-selective store-operated channel that is expressed in T lymphocytes, mast cells, and other hematopoietic cells. In T cells, CRAC channels are essential for generating the prolonged intracellular Ca2+ ([Ca2+](i)) elevation required for the expression of T-cell activation genes. Here we review recent work addressing CRAC channel regulation, pore properties, and the search for CRAC channel genes. Of the current models for CRAC current (I(CRAC)) activation, several new studies argue against a conformational coupling mechanism in which IP(3) receptors communicate store depletion to CRAC channels through direct physical interaction. The study of CRAC channels has been complicated by the fact that they lose activity in the absence of extracellular Ca2+. Attempts to maintain current size by removing intracellular Mg2+ have been found to unmask Mg2+-inhibited cation (MIC/MagNuM/TRPM7) channels, which have been mistaken in several studies for the CRAC channel. Recent studies under conditions that prevent MIC activation reveal that CRAC channels use high-affinity binding of Ca2+ in the pore to achieve high Ca2+ selectivity but have a surprisingly low conductance for both Ca2+ (approximately 10fS) and Na+ (approximately 0.2pS). Pore properties provide a unique fingerprint that provides a stringent test for potential CRAC channel genes and suggest models for the ion selectivity mechanism.

PubMed Disclaimer

Similar articles

See all similar articles

Cited by

See all "Cited by" articles

Publication types

LinkOut - more resources