Description_x000D_ General description_x000D_ Stromal interaction molecule 1 (STIM1) is a conserved single-pass transmembrane protein. STIM1 is expressed ubiquitously in a wide variety of human primary and transformed cell types. STIM1 localizes predominantly in the membrane of the endoplasmic reticulum (ER). It contains an N-terminal EF hand motif located in the ER lumen and appears to function as a sensor of ER Ca2+ levels._x000D_ Immunogen_x000D_ synthetic peptide corresponding to amino acids 657-683 of human STIM1, conjugated to KLH via an N-terminal residue. The corresponding sequence is identical in rat, mouse, bovine, monkey, and dog._x000D_ Application_x000D_ Anti-STIM1 (C-terminal) antibody produced in rabbit has been used in:_x000D_ • western blot_x000D_ • immunoprecipitation_x000D_ • immunofluorescence_x000D_ • immunohistochemistry_x000D_ Physical form_x000D_ Solution in 0.01 M phosphate buffered saline, pH 7.4, containing 15 mM sodium azide._x000D_ Disclaimer_x000D_ Unless otherwise stated in our catalog or other company documentation accompanying the product(s), our products are intended for research use only and are not to be used for any other purpose, which includes but is not limited to, unauthorized commercial uses, in vitro diagnostic uses, ex vivo or in vivo therapeutic uses or any type of consumption or application to humans or animals._x000D_ Biochem/physiol Actions_x000D_ Stromal interaction molecule 1 (STIM1) is required for the activation of store-operated Ca2+ influx. STIM1 undergoes rapid oligomerization and redistributes into discrete spots (punctae) that move towards and accumulate in the cell periphery, possibly to activate Orai1 that is located in the plasma membrane. Overexpression of STIM1 and Orai1 together markedly increases the calcium release-activated channels (CRAC) current (I-CRAC). Dynamic assembly of TRPC1-STIM1-Orai1 ternary complex plays a major role in the activation of store-operated calcium (SOC) channel in response to internal Ca2+ store depletion.