title: Extrapancreatic trypsin-2 cleaves proteinase-activated receptor-2.
abstract: Proteinase-activated receptors (PARs) are activated by proteolytic removal of a short amino terminal peptide, thus exposing a new amino terminus that functions as a tethered ligand that activates the receptor. With the aim to identify and study potential activators of PAR-2 we have developed a new method to measure proteolytic cleavage of PARs. PAR-2 was tagged with the insulin C-peptide that upon receptor cleavage is released and quantified using an ELISA. The modified receptor, shown to be functional in mouse 3T3 cells, was expressed in an insect cell line and the ability of different proteinases to cleave PAR-2 was studied. Two different mast cell tryptases cleaved PAR-2 in a concentration dependent manner, but were much less potent than pancreatic trypsin and trypsin-2 isolated from a carcinoma cell line. Pancreatic trypsin and trypsin-2 were almost equally effective at cleaving PAR-2 suggesting that extrapancreatic trypsins are potential in vivo activators of PAR-2.
authors.affiliation: Division of Molecular Neurobiology, Lund University, Lund, Sweden.
authors.forename: A K
authors.initials: AK
authors.lastname: Alm
authors.forename: R
authors.initials: R
authors.lastname: Gagnemo-Persson
authors.forename: T
authors.initials: T
authors.lastname: Sorsa
authors.forename: J
authors.initials: J
authors.lastname: Sundelin
mesh_terms: D016475:3T3 Cells; D000595:Amino Acid Sequence; D000818:Animals; D002096:C-Peptide / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D002118:Calcium / Q000378:metabolism; D002384:Catalysis; D002417:Cattle; D053818:Chymases; D003110:Colonic Neoplasms / Q000201:enzymology; D004797:Enzyme-Linked Immunosorbent Assay; D006801:Humans; D008407:Mast Cells / Q000201:enzymology; D051379:Mice; D008969:Molecular Sequence Data; D010179:Pancreas / Q000201:enzymology; D044464:Receptor, PAR-2; D018179:Receptors, Thrombin / Q000235:genetics / Q000378:metabolism*; D011993:Recombinant Fusion Proteins / Q000737:chemistry / Q000378:metabolism; D012697:Serine Endopeptidases / Q000378:metabolism; D013917:Thrombin / Q000378:metabolism; D014357:Trypsin / Q000378:metabolism*; D053802:Tryptases; D014407:Tumor Cells, Cultured
chemical_list: D002096:C-Peptide; D044464:Receptor, PAR-2; D018179:Receptors, Thrombin; D011993:Recombinant Fusion Proteins; C509190:Tpsb2 protein, mouse; D012697:Serine Endopeptidases; C083294:chymase 2; D053818:Chymases; D014357:Trypsin; D013917:Thrombin; C509222:Tpsab1 protein, mouse; D053802:Tryptases; D002118:Calcium