Requirement of transforming growth factor-beta (TGF-beta) type II receptor for TGF-beta-induced proliferation and growth inhibition.
Growth regulation of fibroblasts is important for lung development and repair of lung injury. In this study, we investigated the role of transforming growth factor-beta (TGF-beta) type II receptor in the TGF-beta-dependent proliferative response of lung fibroblasts. TGF-beta stimulated the proliferation of adult lung fibroblasts at a low concentration (1 ng/ml), but inhibited the growth of fetal lung fibroblasts in a dose-dependent fashion (0.1-10 ng/ml). Cross-linking and Northern analysis demonstrated that the two lung fibroblast cell lines expressed the TGF-beta type I receptor (T beta RI) and type II receptor (T beta RII). We overexpressed in lung fibroblasts a truncated derivative of T beta RII that lacked the cytoplasmic serine/threonine kinase domain (T beta RII delta K). T beta RII delta K was a dominant-negative inhibitor of TGF-beta signal transduction blocking not only TGF-beta-induced mitogenic action upon adult lung fibroblasts but also TGF-beta-induced growth inhibition of fetal lung fibroblasts. The results indicate that the type II receptor is indispensable for mediating both the mitogenic and antiproliferative effects of TGF-beta upon lung fibroblasts.
Zhao
Y
Y
Department of Medicine, Duke University Medical Center, Durham, North Carolina 27710, USA. zhaoyun@acpub.duke.edu.
Young
S L
SL
D000818:Animals; D001483:Base Sequence; D002455:Cell Division / Q000187:drug effects; D002478:Cells, Cultured; D017931:DNA Primers; D008168:Lung / Q000166:cytology / Q000187:drug effects; D008969:Molecular Sequence Data; D051381:Rats; D018125:Receptors, Transforming Growth Factor beta / Q000378:metabolism*; D016212:Transforming Growth Factor beta / Q000494:pharmacology*
D017931:DNA Primers; D018125:Receptors, Transforming Growth Factor beta; D016212:Transforming Growth Factor beta