title: Platelet-derived growth factor-BB stimulates synthesis of the integrin alpha 2-subunit in human diploid fibroblasts.
abstract: Platelet-derived growth factor (PDGF)-BB stimulates fibroblast-mediated contraction of collagen gels, as well as migration of fibroblasts through collagen-coated membranes. In the present study we examined effects of PDGF-BB stimulation on the synthesis of collagen-binding beta 1 integrins by human diploid fibroblasts (AG 1518). PDGF-BB stimulation led to an increase in the rare of integrin alpha 2-subunit synthesis. In contrast, synthesis of the integrin alpha 1- or alpha 3-subunits were not affected by PDGF-BB stimulation. Furthermore, levels of alpha 2-subunit mRNA relative to levels of glyceraldehyde-3-phosphate dehydrogenase (GAPDH) mRNA increased after PDGF-BB stimulation. The latter finding is compatible with PDGF-BB stimulating transcription of the alpha 2-subunit gene. PDGF-BB stimulation did not influence the relation between levels of integrin beta 1-subunit mRNA and GAPDH mRNA. In addition, the rate of synthesis or post-translational processing of the integrin beta 1-subunit were not, or only marginally, affected by PDGF-BB stimulation. It is likely that the motility response elicited in fibroblasts by PDGF-BB involves such alterations in the synthesis of the alpha 2-subunit of the alpha 2 beta 1 collagen-binding integrin.
authors.affiliation: Department of Medical and Physiological Chemistry, University of Uppsala, Sweden.
authors.forename: K
authors.initials: K
authors.lastname: Ahlén
authors.forename: K
authors.initials: K
authors.lastname: Rubin
mesh_terms: D000077214:Becaplermin; D002460:Cell Line; D003094:Collagen / Q000378:metabolism; D004171:Diploidy; D005347:Fibroblasts / Q000187:drug effects / Q000378:metabolism; D006801:Humans; D039421:Integrin alpha2; D019012:Integrin beta1; D016023:Integrins / Q000096:biosynthesis* / Q000235:genetics / Q000378:metabolism; D010982:Platelet-Derived Growth Factor / Q000494:pharmacology*; D011499:Protein Processing, Post-Translational; D020574:Proto-Oncogene Proteins c-sis; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D011994:Recombinant Proteins / Q000494:pharmacology
chemical_list: D039421:Integrin alpha2; D019012:Integrin beta1; D016023:Integrins; D010982:Platelet-Derived Growth Factor; D020574:Proto-Oncogene Proteins c-sis; D012333:RNA, Messenger; D011994:Recombinant Proteins; D000077214:Becaplermin; D003094:Collagen