Post Translational Modifications | N-glycosylated. N-glycosylation inhibits channel activity in T cells. Ubiquitinated. Cys-195 is oxidated, leading to inactivation of channel activity. |
Function | Pore-forming subunit of two major inward rectifying Ca(2+) channels at the plasma membrane: Ca(2+) release-activated Ca(2+) (CRAC) channels and arachidonate-regulated Ca(2+)-selective (ARC) channels (Probable). Assembles with ORAI2 and ORAI3 to form hexameric CRAC channels that mediate Ca(2+) influx upon depletion of endoplasmic reticulum Ca(2+) store and channel activation by Ca(2+) sensor STIM1, a process known as store-operated Ca(2+) entry (SOCE). Various pore subunit combinations may account for distinct CRAC channel spatiotemporal and cell-type specific dynamics. ORAI1 mainly contributes to the generation of Ca(2+) plateaus involved in sustained Ca(2+) entry and is dispensable for cytosolic Ca(2+) oscillations, whereas ORAI2 and ORAI3 generate oscillatory patterns. CRAC channels assemble in Ca(2+) signaling microdomains where Ca(2+) influx is coupled to calmodulin and calcineurin signaling and activation of NFAT transcription factors recruited to ORAI1 via AKAP5. Activates NFATC2/NFAT1 and NFATC3/NFAT4-mediated transcriptional responses. CRAC channels are the main pathway for Ca(2+) influx in T cells and promote the immune response to pathogens by activating NFAT-dependent cytokine and chemokine transcription. Assembles with ORAI3 to form channels that mediate store-independent Ca(2+) influx in response to inflammatory metabolites arachidonate or its derivative leukotriene C4, termed ARC and LRC channels respectively. Plays a prominent role in Ca(2+) influx at the basolateral membrane of mammary epithelial cells independently of the Ca(2+) content of endoplasmic reticulum or Golgi stores. May mediate transepithelial transport of large quantities of Ca(2+) for milk secretion. Isoform alpha: Pore-forming subunit of both CRAC and ARC channels. Couples Ca(2+) influx to NFAT-mediated transcriptional responses. Isoform beta: Pore-forming subunit of CRAC channels exclusively. |
Protein Name | Calcium Release-Activated Calcium Channel Protein 1Protein Orai-1Transmembrane Protein 142a |
Database Links | Reactome: R-HSA-139853Reactome: R-HSA-5578775Reactome: R-HSA-983695 |
Cellular Localisation | Cell MembraneMulti-Pass Membrane ProteinBasolateral Cell MembraneUpon Store DepletionColocalizes With Stim1 In Membrane Punctae At Er-Pm JunctionsIsoform Alpha: Cell MembraneIsoform Beta: Cell Membrane |
Alternative Antibody Names | Anti-Calcium Release-Activated Calcium Channel Protein 1 antibodyAnti-Protein Orai-1 antibodyAnti-Transmembrane Protein 142a antibodyAnti-ORAI1 antibodyAnti-CRACM1 antibodyAnti-TMEM142A antibody |
Information sourced from Uniprot.org