11 rezultatov
Pathway engineering in medicinal plants attains a special significance in Digitalis species, the main industrial source of cardiac glycosides, steroidal metabolites derived from mevalonic acid via the triterpenoid pathway. In this work, the Arabidopsis thaliana HMG1 cDNA, coding the catalytic domain
Digoxigenin is derived from a plant steroid hormone digoxin found in the plants Digitalis sp. Digoxigenin has been used successfully in labeling nucleic acids. In this experiment we optimized minimum probe requirement for a nonradioactive digoxigenin-based gene detection system in the model plant
The Arabidopsis thaliana VEP1 gene product shows about 70% sequence identity to Digitalis lanata progesterone 5beta-reductase, an enzyme considered to catalyze a key step in the biosynthesis of cardiac glycosides. A. thaliana does not accumulate cardenolides but protein extracts prepared from its
A full-length cDNA clone that encodes progesterone 5beta-reductase (5beta-POR, EC 1.3.1.3) was isolated from ISOPLEXIS CANARIENSIS leaves. The reading frame of the IC5beta-POR gene is 1170 nucleotides corresponding to 389 amino acids. The SPHI /SALI IC5beta-POR fragment was cloned into the pQE
A yeast expression plasmid was constructed containing a cardenolide biosynthetic module, referred to as CARD II, using the AssemblX toolkit, which enables the assembly of large DNA constructs. The genes cloned into the vector were (a) a Δ5 -3β-hydroxysteroid dehydrogenase gene from
PRISEs (progesterone 5β-reductase and/or iridoid synthase-like 1,4-enone reductases) are involved in cardenolide and iridoid biosynthesis. We here investigated a PRISE (rAtSt5βR) from Arabidopsis thaliana, a plant producing neither cardenolides nor iridoids. The structure of rAtSt5βR was elucidated
This paper describes a study into the potential of plants to acclimate to light environments that fluctuate over time periods between 15 min and 3 h. Plants of Arabidopsis thaliana (L.) Heynh., Digitalis purpurea L. and Silene dioica (L.) Clairv. were grown at an irradiance 100 mumol m(-2) s(-1).
Progesterone 5β-reductases (P5βR; EC 1.3.99.6) encoded by Vein Patterning 1 (VEP1) genes are capable of reducing the CC double-bond of a variety of enones enantioselectively. Sequence and activity data of orthologous P5βRs were used to define a set of residues possibly responsible for the large
To understand the molecular mechanisms that control seed formation, we selected a seed-preferential gene (CvADH1) from the ESTs of developing watermelon seeds. RNA blot analysis and in situ localization showed that CvADH1 was preferentially expressed in the nucellar tissue. The CvADH1 protein shared
Most cardenolides used in the therapy of cardiac insufficiency are 5 beta-configured and thus the stereo-specific reduction of the Delta(4,5)-double bond of a steroid precursor is a crucial step in their biosynthesis. This step is thought to be catalysed by progesterone 5 beta-reductases. We report
Vein Patterning 1 (VEP1)-encoded progesterone 5β-reductases/iridoid synthases (PRISE) belong to the short-chain dehydrogenase/reductase superfamily of proteins. They are characterized by a set of highly conserved amino acids in the substrate-binding pocket. All PRISEs are capable of reducing the