Calcitriol enhances transcriptional activity of lysozyme and cathepsin D genes in U937 promonocytes.
Calcitriol (1,25-dihydroxyvitamin D3) has been reported to enhance the rate of synthesis of lysozyme [Rouis, Thomopoulos, Louache, Testa, Heroy & Titeux, (1985) Exp. Cell Res. 157, 539-543] and of cathepsin D [Stein, Braulke, von Figura & Hasilik (1987) Biol. Chem. Hoppe-Seyler 368, 413-418] in human promonocytes U937. In this study we show hat the hormone enhances the steady-state levels of cathepsin D and lysozyme mRNAs. The enhancement of the latter but not of the former is strongly inhibited by cycloheximide. The degradation rates of cathepsin D and lysozyme mRNAs as revealed in the presence of actinomycin D are not significantly affected by the treatment of the cells with calcitriol. In nuclei prepared from calcitriol-treated cells, an enhanced rate of synthesis of cathepsin D and lysozyme mRNA precursors is observed. These results suggest that in human promonocytes the rate of the transcription of cathepsin D and lysozyme genes is enhanced in the presence of calcitriol and that the regulation by the hormone of the transcription of lysozyme gene involves a short-lived or an induced protein.
Redecker
B
B
Institute of Physiological Chemistry and Pathobiochemistry, University of Münster, Federal Republic of Germany.
Horst
M
M
Hasilik
A
A
D002117:Calcitriol / Q000494:pharmacology*; D002402:Cathepsin D / Q000096:biosynthesis*; D002478:Cells, Cultured; D003513:Cycloheximide / Q000494:pharmacology; D003609:Dactinomycin / Q000494:pharmacology; D006801:Humans; D009000:Monocytes / Q000378:metabolism; D009113:Muramidase / Q000096:biosynthesis*; D009693:Nucleic Acid Hybridization; D012322:RNA Precursors / Q000096:biosynthesis; D012333:RNA, Messenger / Q000096:biosynthesis*; D014158:Transcription, Genetic
D012322:RNA Precursors; D012333:RNA, Messenger; D003609:Dactinomycin; D003513:Cycloheximide; D009113:Muramidase; D002402:Cathepsin D; D002117:Calcitriol