Localization and interaction of bovine pancreatic trypsin inhibitor and tryptase in the granules of bovine mast cells.
The interaction of bovine pancreatic trypsin inhibitor and bovine tryptase, isolated from liver capsule mast cells, was investigated. They form a complex in vitro with a Ki of 5.6 nM at pH 8.0 and are localized within the mast cell granules, as shown by immunogold staining at the electron microscope level. In addition, double immunogold electron microscopy revealed that the inhibitor and the enzyme are present in the same granules, where they occur in clusters; this may be taken as an indication of their interaction in vivo and suggests a physiological role for bovine pancreatic trypsin inhibitor in the regulation of tryptase proteolytic activity.
Fiorucci
L
L
Department of Experimental Medicine and Biochemical Sciences, University Tor Vergata, Rome, Italy.
Erba
F
F
Falasca
L
L
Dini
L
L
Ascoli
F
F
D000818:Animals; D007611:Aprotinin / Q000032:analysis* / Q000378:metabolism; D002417:Cattle; D002851:Chromatography, High Pressure Liquid; D053818:Chymases; D003594:Cytoplasmic Granules / Q000201:enzymology*; D004591:Electrophoresis, Polyacrylamide Gel; D006863:Hydrogen-Ion Concentration; D008099:Liver / Q000166:cytology / Q000201:enzymology; D008407:Mast Cells / Q000201:enzymology* / Q000648:ultrastructure; D016253:Microscopy, Immunoelectron; D012697:Serine Endopeptidases / Q000032:analysis* / Q000378:metabolism; D053802:Tryptases
D007611:Aprotinin; D012697:Serine Endopeptidases; C083294:chymase 2; D053818:Chymases; D053802:Tryptases