title: Reduction in platelet-derived growth factor receptor mRNA in v-src-transformed fibroblasts.
abstract: The status of the platelet-derived growth factor (PDGF) receptor in normal rat kidney (NRK) fibroblasts and in NRK fibroblasts transformed by the v-src oncogene or the polyoma middle T (pmt) antigen has been compared. v-src-NRK cells have 7-fold fewer surface binding sites for PDGF than NRK cells, but the affinity of the residual receptors for PDGF is reduced only 2-fold. Levels of the PDGF receptor measured by Western blotting or in an autophosphorylation assay in vitro are 8- and 4-fold lower respectively in v-src-NRK cells than in NRK cells. No PDGF-induced phosphorylation of the PDGF receptor is apparent after 32P-labelling of intact v-src-NRK cells, implying that the reduction in PDGF receptor levels is not a consequence of production of autocrine PDGF. A 10-fold reduction in the amount of mRNA for the PDGF receptor is also observed in v-src-NRK cells. No decrease in PDGF receptor protein or mRNA levels is observed in pmt-NRK cells. We conclude that levels of the PDGF receptor in v-src-transformed NRK fibroblasts are modulated by reduction in the level of PDGF receptor mRNA.
authors.affiliation: Ludwig Institute for Cancer Research, Melbourne Tumour Biology, Royal Melbourne Hospital, Vic., Australia.
authors.forename: Q X
authors.initials: QX
authors.lastname: Zhang
authors.forename: F
authors.initials: F
authors.lastname: Walker
authors.forename: A W
authors.initials: AW
authors.lastname: Burgess
authors.forename: G S
authors.initials: GS
authors.lastname: Baldwin
mesh_terms: D000818:Animals; D002461:Cell Line, Transformed; D015536:Down-Regulation; D009857:Oncogenes; D010766:Phosphorylation; D012333:RNA, Messenger / Q000032:analysis*; D051381:Rats; D017479:Receptors, Platelet-Derived Growth Factor / Q000235:genetics* / Q000378:metabolism
chemical_list: D012333:RNA, Messenger; D017479:Receptors, Platelet-Derived Growth Factor