Anti-Orai1 Antibody Picoband® Fluoro488 Conjugated

ORAI1 (ORAI calcium release-activated calcium modulator 1), also known as CRACM1, TMEM142A, Calcium release-activated calcium channel protein 1, Protein orai-1, Transmembrane protein 142A, FLJ14466, is a calcium selectiveion channelthat in humans is encoded by the ORAI1 gene. Orai1 channels play an important role in the activation of T-lymphocytes. The loss of function mutation of Orai1 causes severe combined immunodeficiency (SCID) in humans. The mammalian orai family has two additional homologs, orai2 and orai3. Orai proteins share no homology with any other ion channel family of any other known proteins. They have 4 transmembrane domains and form tetramers.Prakriya et al. showed that ORAI1 is a PM protein, and that CRAC channel function is sensitive to mutation of 2 conserved acidic residues in the transmembrane segments. Glu106-to-asp (E106D) and glu190-to-gln (E190Q) substitutions in transmembrane helices 1 and 3, respectively, diminished calcium ion influx, increased current carried by monovalent cations, and rendered the channel permeable to cesium ion.Prakriya et al. showed that ORAI1 is a PM protein, and that CRAC channel function is sensitive to mutation of 2 conserved acidic residues in the transmembrane segments.

Detected in T-47D, MDA-MB-175 and HBL-100 breast carcinoma cells, A-431 epidermoid carcinoma cells, SW48 and SNU-C2B colon carcinoma cells and Hs 294T melanoma cells (at protein level) . Expressed at low levels in most adult tissues and is highest in the brain, lung, placenta and kidney. Lower levels of expression are detected in melanocytes, heart, liver, skeletal muscle and pancreas. Abundant in breast carcinoma cell lines. In the colonic mucosa, expressed in epithelia but not in the connective tissue of the lamina propria. In the thyroid gland, expressed in the epithelium of the thyroid follicles. In pancreas, expressed in the islets of Langerhans cells, but not in the surrounding epithelial cells of the exocrine pancreas. In kidney, expressed in the epithelia of the distal tubules. Not expressed in connective tissue, endothelial cells, adipose tissue, muscle cells or cells of hematopoietic origin.

Angiogenesis, Cancer, Cancer Metabolism, Cardiovascular, Growth Factors, Growth Factors/Hormones, Hematopoietic Progenitors, Host-Virus Interaction, Interspecies Interaction, Invasion/Microenvironment, Metabolism, Metabolism Processes, Microbiology, Oncoproteins, Oncoproteins/Suppressors, Pathways and Processes, Protein Phosphorylation, Receptor Tyrosine Kinases, Response To Hypoxia, Signal Transduction, Stem Cells, Surface Molecules, Tyrosine Kinases

Ca2+ release-activated Ca2+ (CRAC) channel subunit which mediates Ca2+ influx following depletion of intracellular Ca2+ stores and channel activation by the Ca2+ sensor, STIM1. CRAC channels are the main pathway for Ca2+ influx in T-cells and promote the immune response to pathogens by activating the transcription factor NFAT.

1. Prakriya, M., Feske, S., Gwack, Y., Srikanth, S., Rao, A., Hogan, P. G. Orai1 is an essential pore subunit of the CRAC channel. Nature 443: 230-233, 2006.