Interhelical interactions within the STIM1 CC1 domain modulate CRAC channel activation.
Nat Chem Biol
; 17(2): 196-204, 2021 02.
Article
in En
| MEDLINE
| ID: mdl-33106661
ABSTRACT
The calcium release activated calcium channel is activated by the endoplasmic reticulum-resident calcium sensor protein STIM1. On activation, STIM1 C terminus changes from an inactive, tight to an active, extended conformation. A coiled-coil clamp involving the CC1 and CC3 domains is essential in controlling STIM1 activation, with CC1 as the key entity. The nuclear magnetic resonance-derived solution structure of the CC1 domain represents a three-helix bundle stabilized by interhelical contacts, which are absent in the Stormorken disease-related STIM1 R304W mutant. Two interhelical sites between the CC1α1 and CC1α2 helices are key in controlling STIM1 activation, affecting the balance between tight and extended conformations. Nuclear magnetic resonance-directed mutations within these interhelical interactions restore the physiological, store-dependent activation behavior of the gain-of-function STIM1 R304W mutant. This study reveals the functional impact of interhelical interactions within the CC1 domain for modifying the CC1-CC3 clamp strength to control the activation of STIM1.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Stromal Interaction Molecule 1
/
Calcium Release Activated Calcium Channels
/
Neoplasm Proteins
Limits:
Humans
Language:
En
Journal:
Nat Chem Biol
Journal subject:
BIOLOGIA
/
QUIMICA
Year:
2021
Document type:
Article
Affiliation country:
Austria