Superinduction of alpha 2u globulin by actinomycin D: evidence for drug-mediated increase in alpha 2u mRNA.
Actinomycin D, an inhibitor of DNA-dependent RNA synthesis, increased the hepatic concentration of alpha 2u globulin, an androgen-inducible protein in the rat. Spayed female rats with a marginally induced state of alpha 2u synthesis showed an approximately 5-fold increase in hepatic alpha 2u globulin within 3-6 hr after treatment with actinomycin D. Initial treatment of these animals with 5 alpha-dihydrotestosterone, followed by actinomycin D, resulted within 2-3 hr in a more than 2-fold increase in hepatic alpha 2u globulin compared to animals treated with the androgen alone. In spite of inhibition of hepatic synthesis of poly(A)-containing RNA to less than 25% of control, superinduction with actinomycin D resulted in a parallel increase in the translatable mRNA for alpha 2u globulin. These results showing increase in both alpha 2u globulin and its translatable mRNA after superinduction with actinomycin D support the concept of post-transcriptional repression of alpha2u synthesis.
D000510:Alpha-Globulins / Q000096:biosynthesis*; D000546:Amanitins / Q000494:pharmacology; D000818:Animals; D002369:Castration; D003513:Cycloheximide / Q000494:pharmacology; D003609:Dactinomycin / Q000494:pharmacology*; D003839:Deoxyadenosines / Q000494:pharmacology; D005260:Female; D008099:Liver / Q000187:drug effects / Q000378:metabolism*; D009963:Orotic Acid / Q000378:metabolism; D014176:Protein Biosynthesis / Q000187:drug effects*; D012333:RNA, Messenger / Q000378:metabolism*; D051381:Rats; D014158:Transcription, Genetic / Q000187:drug effects
D000510:Alpha-Globulins; D000546:Amanitins; D003839:Deoxyadenosines; D012333:RNA, Messenger; D003609:Dactinomycin; D009963:Orotic Acid; D003513:Cycloheximide