title: Cytokinin oxidase activity and cytokinin content in roots of sunflower under water stress.
abstract: Contents of trans-zeatin riboside (ZR), dihydrozeatin riboside (DZR) and N6-(delta2-isopentenyl) adenosine (iPA) was quantified by an indirect ELISA using polyclonal antibodies, in the roots, xylem sap and leaves of pot grown sunflower plants subjected to water stress (RWC of leaves approximately 65 per cent). The delivery rates of all three cytokinins decreased significantly under stress. Cytokinin levels also decreased in roots and in leaves of stressed plants. Three-fold increase in cytokinin oxidase activity was observed in stressed roots after polymin P-ammonium sulphate fractionation. Further purification using Con A agarose resulted in elution of protein with cytokinin oxidase activity and was found to be 30 kDa protein on SDS-PAGE.
authors.affiliation: Department of Crop Physiology, University of Agricultural Sciences, Bangalore, India.
authors.forename: R V
authors.initials: RV
authors.lastname: Manju
authors.forename: M J
authors.initials: MJ
authors.lastname: Kulkarni
authors.forename: T G
authors.initials: TG
authors.lastname: Prasad
authors.forename: L
authors.initials: L
authors.lastname: Sudarshana
authors.forename: V R
authors.initials: VR
authors.lastname: Sashidhar
mesh_terms: D002846:Chromatography, Affinity; D002851:Chromatography, High Pressure Liquid; D003583:Cytokinins / Q000378:metabolism*; D004591:Electrophoresis, Polyacrylamide Gel; D004797:Enzyme-Linked Immunosorbent Assay; D006368:Helianthus; D010088:Oxidoreductases / Q000302:isolation & purification / Q000378:metabolism*; D014867:Water
chemical_list: D003583:Cytokinins; D014867:Water; D010088:Oxidoreductases; C019984:cytokinin oxidase