PAR1 Rabbit Polyclonal Antibody

Function

PAR1 is a transmembrane G-protein-coupled receptor (GPCR) that shares much of its structure with the other protease-activated receptors. These characteristics include having seven transmembrane alpha helices, four extracellular loops and three intracellular loops. PAR1 specifically contains 425 amino acid residues arranged for optimal binding of thrombin at its extracellular N-terminus. The C-terminus of PAR1 is located on the intracellular side of the cell membrane as part of its cytoplasmic tail. PAR1 is activated when the terminal 41 amino acids of its N-terminus are cleaved by thrombin, a serine protease. Once cleaved, PAR1 can activate G-proteins that bind to several locations on its intracellular loops. For example, PAR1 in conjunction with PAR4 can couple to and activate G-protein G12/13 which in turn activates Rho and Rho kinase. Additionally, both PAR1 and PAR4 can couple to G-protein q which stimulates intracellular movement for Calcium ions that serve as second messengers for platelet activation. The phosphorylation of PAR1's cytoplasmic tail and subsequent binding to arrestin uncouples the protein from G protein signaling. These phosphorylated PAR1s are transported back into the cell via endosomes where they are sent to Golgi bodies.

Background References

1. Schweickert PG. et. al. Thrombin-PAR1 signaling in pancreatic cancer promotes an immunosuppressive microenvironment. J Thromb Haemost. 2021 Jan

2. Alvarez-Arce A. et. al. Thrombin-activated PAR1 membrane expression is regulated by Rab11a-RCP complex dissociation. Cell Signal. 2020 Nov

Subcellular Location

Cell membrane.

UNIPROT

SwissProt: P25116 Human

SwissProt: P30558 Mouse

SwissProt: P26824 Rat

Synonyms