A dual mechanism promotes switching of the Stormorken STIM1 R304W mutant into the activated state

STIM1 and Orai1 are key components of the Ca 2+ -release activated Ca 2+ (CRAC) current. Orai1, which represents the subunit forming the CRAC channel complex, is activated by the ER resident Ca 2+ sensor STIM1. The genetically inherited Stormorken syndrome disease has been associated with the STIM1 single point R304W mutant. The resulting constitutive activation of Orai1 mainly involves the CRAC-activating domain CAD/SOAR of STIM1, the exposure...