Inhibition of Cytokinin-Glucose Conjugation in Derooted Radish, Tobacco and Bean Seedlings

0172321 - UEB-Q 20033046 RIV BG eng J - Journal Article
Blagoeva, Elitsa - Dobrev, Petre - Vaňková, Radomíra
Inhibition of Cytokinin-Glucose Conjugation in Derooted Radish, Tobacco and Bean Seedlings.
Bulgarian Journal of Plant Physiology. Roč. 29, 1/2 (2003), s. 13-20. ISSN 1310-4586
R&D Projects: GA ČR GA522/99/1130; GA ČR GP522/02/D058; GA MŠMT LN00A081
Institutional research plan: CEZ:AV0Z5038910
Keywords : dihydrozeatin * cyclin-dependent kinase inhibitors * radish (Raphanus sativus L.)
Subject RIV: EB - Genetics ; Molecular Biology

Four inhibitors of cyclin-dependent kinases, olomoucine, bohem-ine, roscovitine and isopropyl-olomoucine were tested for their ability to modify the conversion of exogenous tritiated dihydrozeatin ([3H]DHZ) in species differing in their pattern of cytokinin sequestering. In radish (Raph-anus sativus L.), species with predominant cytokinin N-glucosylation pathway, application of inhibitors (lOOuM) decreased conversion of [3H]DHZ into 7N- and 9N-glucosides. In common bean (Phaseolus vulgaris L.) cytokinin O-glucosylation is the prevailing deactivation mechanism and the tested inhibitors did not influence significantly the conversion of [3H]DHZ. The down-regulation of active cytokinin levels in tobacco (Nicotiana tabacum L.) is achieved by both 7N-glucosylation and degradation by cytokinin oxid-ase/dehydrogenase (CKX). The inhibition of 7N-glucosylation in this species stimulated the conversion of [3H]DHZ to nucleotide and riboside. The tested purine analogues have been proved to be selective inhibitors of cytokinin N-glucosylation with potential practical application.
Permanent Link: http://hdl.handle.net/11104/0069360