Suppression of platelet-derived growth factor alpha- and beta-receptor mRNA levels in human fibroblasts by SV40 T/t antigen.
It is known that down-regulation of cell surface platelet-derived growth factor (PDGF) receptors accompanies transformation by SV40. In this work human embryonic lung fibroblasts were used as a model system to study the effects of SV 40 on PDGF receptor expression. It is shown that transformation by SV 40 early region leads to a total loss of PDGF alpha-receptor and partial loss of beta-receptor mRNA. Microinjection experiments revealed that receptor down-regulation was a primary effect, and not only secondary to transformation and clonal selection. Total loss of PDGF alpha-receptor expression requires both large T and small t, and down-regulation of the PDGF alpha-receptor occurs independently of p53 and Rb binding to large T.
Wang
J L
JL
Department of Pathology, University Hospital, Uppsala, Sweden.
Nistér
M
M
Bongcam-Rudloff
E
E
Pontén
J
J
Westermark
B
B
D000952:Antigens, Polyomavirus Transforming / Q000502:physiology*; D001665:Binding Sites / Q000502:physiology; D015536:Down-Regulation / Q000502:physiology; D004622:Embryo, Mammalian / Q000166:cytology; D005347:Fibroblasts / Q000166:cytology / Q000648:ultrastructure; D015967:Gene Expression Regulation, Viral / Q000502:physiology; D006801:Humans; D008168:Lung / Q000166:cytology; D009154:Mutation / Q000502:physiology; D011120:Polyomavirus / Q000276:immunology*; D012333:RNA, Messenger / Q000378:metabolism; D017479:Receptors, Platelet-Derived Growth Factor / Q000037:antagonists & inhibitors / Q000235:genetics*; D016160:Retinoblastoma Protein / Q000378:metabolism; D013997:Time Factors; D014170:Transformation, Genetic / Q000502:physiology; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism
D000952:Antigens, Polyomavirus Transforming; D012333:RNA, Messenger; D016160:Retinoblastoma Protein; D016159:Tumor Suppressor Protein p53; D017479:Receptors, Platelet-Derived Growth Factor