Expression of 3beta-HSD and P5betaR, genes respectively coding for Delta5-3beta-hydroxysteroid dehydrogenase and progesterone 5beta-reductase, in leaves and cell cultures of Digitalis lanata EHRH.
Plants of the genus Digitalis produce 5 beta-cardenolides that are used in the therapy of cardiac insufficiency in humans. 3 beta-Hydroxysteroid dehydrogenase (3 beta-HSD) and progesterone 5 beta-reductase (P5 betaR) are both supposed to be important enzymes in the biosynthesis of these natural products. Activity and gene expression were demonstrated for both enzymes in cardenolide-accumulating leaves of Digitalis lanata but also in cardenolide-free permanent cell suspension cultures initiated from D. lanata leaf tissue. Enzyme activities were determined and quantified by HPLC and GC-MS methods. Expression of the respective genes, namely AY585867.1 (P5betaR gene) and DQ466890.1 (3beta-HSD gene), was made evident by real-time polymerase chain reaction (qPCR) analysis. We demonstrate for the first time that the P5betaR gene, encoding an enzyme described as a key enzyme in cardenolide biosynthesis, is also expressed in cardenolide-free tissues of cardenolide-containing plants.
Lehrstuhl für Pharmazeutische Biologie, Department Biologie, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany.
Mona
M
Ernst
Rodrigo Maia
RM
de Padua
Vanessa
V
Herl
Frieder
F
Müller-Uri
Wolfgang
W
Kreis
D015096:3-Hydroxysteroid Dehydrogenases / Q000235:genetics / Q000378:metabolism*; D002298:Cardenolides / Q000378:metabolism*; D018929:Cell Culture Techniques; D004070:Digitalis / Q000201:enzymology / Q000235:genetics* / Q000378:metabolism; D015870:Gene Expression; D017343:Genes, Plant; D010088:Oxidoreductases / Q000235:genetics / Q000378:metabolism*; D018515:Plant Leaves; D020133:Reverse Transcriptase Polymerase Chain Reaction
D002298:Cardenolides; D010088:Oxidoreductases; D015096:3-Hydroxysteroid Dehydrogenases; C090493:progesterone 5 beta-reductase