title: Function of the type V transforming growth factor beta receptor in transforming growth factor beta-induced growth inhibition of mink lung epithelial cells.
abstract: The type V transforming growth factor beta (TGF-beta) is a 400-kDa nonproteoglycan membrane protein that co-expresses with the type I, type II, and type III TGF-beta receptors in most cell types. The type V TGF-beta receptor exhibits a Ser/Thr-specific protein kinase activity with distinct substrate specificity (Liu, Q., Huang, S. S., and Huang, J. (1994) J. Biol. Chem. 269, 9221-9226). In mink lung epithelial cells, the type V TGF-beta receptor was found to form heterocomplexes with the type I TGF-beta receptor by immunoprecipitation with antiserum to the type V TGF-beta receptor after 125I-TGF-beta affinity labeling or Trans35S-label metabolic labeling of the cells. The kinase activity of the type V TGF-beta receptor was stimulated after treatment of mink lung epithelial cells with TGF-beta. TGF-beta stimulation resulted in the growth inhibition of wild-type mink lung epithelial cells and to a lesser extent of the type I and type II TGF-beta receptor-defective mutants, although higher concentrations of TGF-beta were required for the growth inhibition of these mutants. TGF-beta was unable to induce growth inhibition in human colorectal carcinoma cells lacking the type V TGF-beta receptor but expressing the type I and type II TGF-beta receptors. These results suggest that the type V TGF-beta receptor can mediate the TGF-beta-induced growth inhibitory response in the absence of the type I or type II TGF-beta receptor. These results also support the hypothesis that loss of the type V TGF-beta receptor may contribute to the malignancy of certain carcinoma cells.
authors.affiliation: Department of Biochemistry and Molecular Biology, St. Louis University School of Medicine, St. Louis, Missouri 63104, USA.
authors.forename: Q
authors.initials: Q
authors.lastname: Liu
authors.forename: S S
authors.initials: SS
authors.lastname: Huang
authors.forename: J S
authors.initials: JS
authors.lastname: Huang
mesh_terms: D030201:Activin Receptors, Type I; D000818:Animals; D002417:Cattle; D002455:Cell Division / Q000187:drug effects; D004848:Epithelium / Q000187:drug effects; D006801:Humans; D008168:Lung / Q000166:cytology* / Q000187:drug effects; D008907:Mink; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism; D011509:Proteoglycans / Q000378:metabolism; D000077293:Receptor, Transforming Growth Factor-beta Type I; D000077294:Receptor, Transforming Growth Factor-beta Type II; D018125:Receptors, Transforming Growth Factor beta / Q000378:metabolism*; D016212:Transforming Growth Factor beta / Q000494:pharmacology*; D014407:Tumor Cells, Cultured
chemical_list: D011509:Proteoglycans; D018125:Receptors, Transforming Growth Factor beta; D016212:Transforming Growth Factor beta; C071736:betaglycan; D017346:Protein Serine-Threonine Kinases; D030201:Activin Receptors, Type I; D000077293:Receptor, Transforming Growth Factor-beta Type I; D000077294:Receptor, Transforming Growth Factor-beta Type II