title: Regulation of transglutaminase activity by GTP in digitonin permeabilized Yoshida tumor cells.
abstract: Yoshida tumor cells contain consistent amounts of type 2 transglutaminase, along with a membrane bound form of the enzyme. Digitonin permeabilized cells retain a large proportion of type 2 TGase and of substrate proteins which are labelled by radioactive putrescine in the presence of calcium. GTP inhibits protein labelling at low calcium concentration by inhibiting type 2 TGase without affecting membrane-bound TGase. These results support the notion that inhibition of type 2 TGase by GTP is physiologically relevant.
authors.affiliation: Institute of Biological Chemistry, University of Ferrara, Italy.
authors.forename: C M
authors.initials: CM
authors.lastname: Bergamini
authors.forename: M
authors.initials: M
authors.lastname: Signorini
authors.forename: L
authors.initials: L
authors.lastname: Caselli
authors.forename: P
authors.initials: P
authors.lastname: Melandri
mesh_terms: D000818:Animals; D001665:Binding Sites / Q000187:drug effects; D002118:Calcium / Q000378:metabolism; D002462:Cell Membrane / Q000187:drug effects; D002463:Cell Membrane Permeability; D004072:Digitonin / Q000494:pharmacology*; D006160:Guanosine Triphosphate / Q000494:pharmacology*; D011700:Putrescine / Q000378:metabolism; D051381:Rats; D012517:Sarcoma, Yoshida / Q000201:enzymology*; D011503:Transglutaminases / Q000378:metabolism*; D014407:Tumor Cells, Cultured
chemical_list: D006160:Guanosine Triphosphate; D011503:Transglutaminases; D004072:Digitonin; D002118:Calcium; D011700:Putrescine