Glucocorticoid regulation of rRNA synthesis.
Glucocorticoids inhibit transcription of the genes encoding rRNA (rDNA) in P1798 lymphoma cells. This is due to a decrease in the amount or activity of a transcription factor, called TFIC. TFIC has been purified to apparent homogeneity and the properties of this protein have been investigated in detail. TFIC is tightly associated with RNA polymerase I. The data indicate that TFIC is a bona fide initiation factor that is required for formation of the first phosphodiester bond of nascent pre-rRNA. Extracts from dexamethasone-treated cells are devoid of this factor and cannot form initiated complexes in vitro.
Department of Human Biological Chemistry and Genetics, University of Texas Medical Branch, Galveston.
P B
PB
Mahajan
E A
EA
Thompson
D000818:Animals; D005938:Glucocorticoids / Q000502:physiology*; D006493:Heparin / Q000494:pharmacology; D007700:Kinetics; D051379:Mice; D011189:Potassium Chloride / Q000494:pharmacology; D012335:RNA, Ribosomal / Q000096:biosynthesis*; D013953:Thymus Neoplasms; D014158:Transcription, Genetic / Q000187:drug effects; D014407:Tumor Cells, Cultured
D005938:Glucocorticoids; D012335:RNA, Ribosomal; D011189:Potassium Chloride; D006493:Heparin