Inositol 1,4,5-trisphosphate receptor type 1 (UniProt: P29994; also known as IP3 receptor isoform 1, IP-3-R, IP3R 1, InsP3R1, Type 1 inositol 1,4,5-trisphosphate receptor, Type 1 InsP3 receptor) is encoded by the Itpr1 (also known as Insp3r) gene (Gene ID: 25262) in rat. InsP3R1 is a multi-pass membrane protein located on endoplasmic reticulum (ER) membrane. Its highest levels are found in neurons, with very high expression in the Purkinje cells of the cerebellum. InsP3R1 contains a calcium channel in its C-terminal extremity. It has a large N-terminal cytoplasmic region that has the ligand-binding site in the N-terminus and modulatory sites in the middle portion immediately upstream of the channel region. InsP3R1 serves as an intracellular channel that mediates calcium release from the endoplasmic reticulum following stimulation by inositol 1,4,5-trisphosphate.It is involved in the regulation of epithelial secretion of electrolytes and fluid through the interaction with AHCYL1. It also plays a role in ER stress-induced apoptosis wherein cytoplasmic calcium released from the ER triggers apoptosis by the activation of CaM kinase II, eventually leading to the activation of downstream apoptosis pathways. InsP3R1 is phosphorylated by cAMP-dependent protein kinase (PKA), which increases the interaction with inositol 1,4,5-trisphosphate and reduces the interaction with AHCYL1. This prevents the ligand-induced opening of the calcium channels. Calcium appears to inhibit ligand binding to the receptor, most probably by interacting with a distinct calcium-binding protein which then inhibits the receptor. Reduced expression of InsP3R1 has been reported in cisplatin-resistant cancer cells and overexpression of InsP3R1 in resistant cells induces apoptosis and increases sensitivity to cisplatin. (Ref.: Tsunoda T., et al. (2005). Oncogene. 24(8):1396-402; Wang, Y., et al. (2001). Cir. Res. 88(2): 202-209).
Synonyms: Inositol 1, 4, 5-trisphosphate receptor type I, IP3 receptor isoform 1, IP-3-R1, InsP3R1, Type 1 inositol 1, 4, 5-trisphosphate receptor, Type 1 InsP3 receptor
Application: Western Blotting Analysis: A 1:1,000 dilution from a representative lot detected IP3R1 in 10 µg of rat and mouse brain microsomal preparation.Western Blotting Analysis: A representative lot detected IP3R1 in bovine salivary gland, DT40 3KO cells stably expressing IP3R1 (Chandrasekhar, R., et. al. (2016). J Biol Chem. 291(10):4846-60).Immunohistochemistry Analysis: A 1:1,000 dilution from a representative lot detected IP3R1 in human brain and rat brain tissues.Immunoprecipitation Analysis: A representative lot detected IP3R1 in bovine salivary gland (Chandrasekhar, R., et. al. (2016). J Biol Chem. 291(10):4846-60).
Other Notes: Concentration: Please refer to lot specific datasheet.