The ITPR3 (Inositol 1.4.5-Trisphosphate Receptor Type 3) antibody is a research tool targeting the ITPR3 protein, a calcium release channel located in the endoplasmic reticulum membrane. As one of three isoforms (ITPR1-3) in the IP3 receptor family, ITPR3 is activated by inositol trisphosphate (IP3), a secondary messenger in signaling pathways. It mediates calcium ion (Ca²⁺) flux into the cytoplasm, regulating processes like apoptosis, secretion, and gene expression. ITPR3 is distinguished by its tissue-specific expression, predominantly in gastrointestinal epithelia, kidneys, and ovaries, and its unique kinetic properties in calcium signaling compared to ITPR1/ITPR2.
Antibodies against ITPR3 are widely used to study its role in physiological and pathological contexts, including cancer, neurodegenerative diseases, and metabolic disorders. For example, ITPR3 dysregulation has been linked to tumor progression in colorectal and pancreatic cancers. Researchers employ these antibodies in techniques such as Western blotting, immunohistochemistry, and immunofluorescence to map protein expression, localization, and interaction networks. Commercial ITPR3 antibodies are typically validated for specificity using knockout controls or siRNA-mediated silencing. Challenges include cross-reactivity with other isoforms due to structural homology, necessitating careful validation. Ongoing research explores ITPR3's therapeutic potential, with its antibodies serving as critical tools for mechanistic insights and biomarker discovery.