STIM1 (G555) Antibody detects endogenous levels of total STIM1 protein.
Source / Purification
Polyclonal antibodies are produced by immunizing animals with a synthetic peptide corresponding to the region surrounding Gly555 of human STIM1 protein. Antibodies are purified by protein A and peptide affinity chromatography.
Background
Ca2+ is a key second messenger in many intracellular signaling pathways. Ca2+ signals control many cellular functions ranging from short-term responses such as contraction and secretion to longer-term regulation of cell growth and proliferation (1,2). Stromal interaction molecules (STIMs) function as Ca2+ sensors that detect changes in Ca2+ content in intracellular Ca2+ stores (3). STIM1 is conserved, ubiquitously expressed, and functions as an endoplasmic reticulum (ER) Ca2+ sensor that migrates from the ER Ca2+ store to the plasma membrane where it activates calcium-release-activated calcium (CRAC) channels when the ER Ca2+ store is low (4). STIM1 is a potential tumor suppressor; defects in STIM1 may cause rhabdomyosarcoma and rhabdoid tumors (5). STIM1 can either homodimerize or form heterodimers with STIM2. STIM2 possesses a high sequence identity to STIM1 and can function as an inhibitor of STIM1-mediated plasma membrane store-operated Ca2+ entry (6). However, further investigation is required to elucidate the true physiological function of STIM2.