Open AccessCa2+/Calmodulin Binding to STIM1 Hydrophobic Residues Facilitates Slow Ca2+-Dependent Inactivation of the Orai1 Channel
Author(s) -
Rajesh Bhardwaj,
Bartłomiej Augustynek,
Ebru Ercan-Herbst,
K. Palanivel,
Matthias Seedorf,
Christine Peinelt,
Matthias A. Hediger
Publication year - 2020
Publication title -
cellular physiology and biochemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.486
H-Index - 87
eISSN - 1421-9778
pISSN - 1015-8987
DOI - 10.33594/000000218
Subject(s) - orai1 , stim1 , calmodulin , chemistry , microbiology and biotechnology , patch clamp , biophysics , hek 293 cells , gating , biochemistry , endoplasmic reticulum , biology , receptor , enzyme
Store-operated Ca 2+ entry (SOCE) through plasma membrane Ca 2+ channel Orai1 is essential for many cellular processes. SOCE, activated by ER Ca 2+ store-depletion, relies on the gating function of STIM1 Orai1-activating region SOAR of the ER-anchored Ca 2+ -sensing protein STIM1. Electrophysiologically, SOCE is characterized as Ca 2+ release-activated Ca 2+ current (I CRAC ). A major regulatory mechanism that prevents deleterious Ca 2+ overload is the slow Ca 2+ -dependent inactivation (SCDI) of I CRAC . Several studies have suggested a role of Ca 2+ /calmodulin (Ca 2+ /CaM) in triggering SCDI. However, a direct contribution of STIM1 in regulating Ca 2+ /CaM-mediated SCDI of I CRAC is as yet unclear.