STIM proteins contain a single SAM (sterile alpha-motif) domain and an unpaired EF hand within the highly conserved extracellular region, and the coiled-coil domains thatare conserved in structure and position within the cytoplasmic region []. The EF-hand and SAM domain of the STIM proteins serves as a Ca2+ sensory region []. "Hidden"EF hand and SAM domains have a stable intramolecular association. Destabilization of the EF-SAM association during Ca2+ depletion leads to partial unfolding and aggregation (homooligomerization) []. STIM oligomerization is a key induction step in the activation of Ca(2+)-permeable channels on the plasma membrane. In human cells, STIM1 and STIM2 are regulators of store-operated calcium (Ca(2+)) entry as well as basal cytoplasmic Ca(2+) levels [].
STIM proteins contain a single SAM (sterile alpha-motif) domain and an unpaired EF hand within the highly conserved extracellular region, and the coiled-coil domains that are conserved in structure and position within the cytoplasmic region []. The EF-hand and SAM domain of the STIM proteins serves as a Ca2+ sensory region []. "Hidden"EF hand and SAM domains have a stable intramolecular association. Destabilization of the EF-SAM association during Ca2+ depletion leads to partial unfolding and aggregation (homooligomerization) []. STIM oligomerization is a key induction step in the activation of Ca(2+)-permeable channels on the plasma membrane. In human cells, STIM1 and STIM2 are regulators of store-operated calcium (Ca(2+)) entry as well as basal cytoplasmic Ca(2+) levels [].This entry represents the SAM domain of STIM2.
