The GC factor regulates the expression of the insulin-like growth factor-I receptor.
We have transfected a plasmid expressing the transcriptional regulator GC Factor (GCF) into cell lines and have found that the GCF: 1 causes a decrease in the levels of insulin-like growth factor I receptor (IGF-IR) mRNA; 2 causes a decrease in the number of IGF-IRs; and 3 represses the activity of the IGF-IR promoter. In addition, we show that the regulation of IGF-IR expression by GCF plays a physiological role in the control of cellular proliferation in vitro.
Morrione
A
A
Jefferson Cancer Center, Thomas Jefferson University, Philadelphia, PA 19107, USA.
DeAngelis
T
T
Baserga
R
R
D000818:Animals; D001483:Base Sequence; D002455:Cell Division / Q000187:drug effects; D016895:Culture Media, Serum-Free / Q000494:pharmacology; D004815:Epidermal Growth Factor / Q000494:pharmacology; D066246:ErbB Receptors / Q000096:biosynthesis / Q000235:genetics; D005347:Fibroblasts / Q000187:drug effects / Q000378:metabolism; D005786:Gene Expression Regulation / Q000187:drug effects; D051379:Mice; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D017526:Receptor, IGF Type 1 / Q000096:biosynthesis* / Q000235:genetics; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D012097:Repressor Proteins / Q000096:biosynthesis / Q000235:genetics / Q000502:physiology*; D014158:Transcription, Genetic / Q000187:drug effects; D014162:Transfection
D016895:Culture Media, Serum-Free; C072278:GCFC2 protein, human; D011993:Recombinant Fusion Proteins; D012097:Repressor Proteins; D004815:Epidermal Growth Factor; D066246:ErbB Receptors; D017526:Receptor, IGF Type 1