Glucocorticoid-induced changes in liver: effect of dexamethasone administration on DNA topoisomerase I and II activities and distribution of histone H1 subtypes.
The activities of DNA topoisomerase I and II and the relative proportions of the histone H1 subtypes were investigated in rat liver which was undergoing hypertrophy and exhibiting increased transcriptional activity following the administration of dexamethasone. There was a rise in the level of activity of DNA topoisomerase I and a slight fall in that of DNA topoisomerase II. The relative proportions of the H1 subtypes were altered due to a preferential increase in H1.1. The results are discussed in relation to the effect of glucocorticoids on the transcription and replication of hepatic DNA.
Division of Cellular and Molecular Biology, School of Biological and Medical Sciences, University of St. Andrews, Fife, UK.
G A
GA
Goodlad
C M
CM
Clark
D000818:Animals; D002467:Cell Nucleus / Q000378:metabolism; D004261:DNA Replication / Q000187:drug effects; D004264:DNA Topoisomerases, Type I / Q000378:metabolism*; D004250:DNA Topoisomerases, Type II / Q000378:metabolism*; D012321:DNA-Directed RNA Polymerases / Q000032:analysis; D003907:Dexamethasone / Q000494:pharmacology*; D005260:Female; D006657:Histones / Q000032:analysis*; D008099:Liver / Q000187:drug effects* / Q000201:enzymology / Q000648:ultrastructure; D051381:Rats; D017208:Rats, Wistar
D006657:Histones; D003907:Dexamethasone; D012321:DNA-Directed RNA Polymerases; D004264:DNA Topoisomerases, Type I; D004250:DNA Topoisomerases, Type II