Regulators of cell division in plant tissues. XXX. Cytokinin metabolism in relation to radish cotyledon expansion and senescence

摘要: Kinetic studies of formation glucosides 6-benzylaminopurine (BAP) in excised radish cotyledons indicated that the 3-, 7-, and 9-glucosides (N-glucosides) were each formed directly from BAP. The 7- BAP 7-glucoside zeatin exhibited great stability cotyledons, but 3-glucoside was converted to free When3H-labeled supplied developed at high concentrations (100 μM), 7-glucosylzeatin principal metabolite, an appreciable proportion extracted3H due O-glucosylzeatin. In immature as used cotyledon cytokinin bioassay, this O-glucoside shown be into probably via zeatin. Metabolism studied relation cytokinin-induced expansion. Cytokinin N-glucosides not metabolites responsible for observed expansion, detoxification products, or deactivation products which coupled with action. However, base, its riboside, nucleotide possible active forms associated significance is discussed. Senescent nonsenescent differed their metabolism BAP, zeatin, riboside. Senescence principally a reduction ability form 7-glucosylzeatin, enhanced adenine derivatives, inability amounts 3-glucosyl-BAP. A two-dimensional thin layer chromatography (TLC) system, based on adjoining layers cellulose silica gel, separating described. This does completely separate riboside corresponding dihydro-compounds. reversed phase TLC method achieving these separations also reported.