title: A new family of cytokinin receptors from Cereales.
abstract: The highly specific recognition of a natural cytokinin, trans-zeatin, by cytokinin-binding protein (CBP) of 67 kDa from barley leaves was detected with an assay developed on the basis of cytokinin competition in ELISA with anti-idiotype antibodies (raised against antibodies to zeatin) for complex formation with CBP. Monoclonal antibodies (mAbs) raised against 70 kDa CBP from etiolated maize seedlings cross-reacted with barley 67 kDa CBP and prevented barley CBP and trans-zeatin induced activation of transcription elongation directed by RNA polymerase I associated with barley chromatin. One mAb (Z-6) had an agonistic effect. Maize CBP replaced barley CBP in activation of RNA synthesis with cytokinin in the barley transcription system. Hence, a new family of cytokinin receptors with common functions and immunodeterminants including maize and barley CBPs was found.
authors.affiliation: Timiryazev Institute of Plant Physiology, Russian Academy of Sciences, Moscow. vladimir@ad.plantphys.msk.ru
authors.forename: O N
authors.initials: ON
authors.lastname: Kulaeva
authors.forename: T K
authors.initials: TK
authors.lastname: Zagranichnaya
authors.forename: F A
authors.initials: FA
authors.lastname: Brovko
authors.forename: N N
authors.initials: NN
authors.lastname: Karavaiko
authors.forename: S Y
authors.initials: SY
authors.lastname: Selivankina
authors.forename: Y V
authors.initials: YV
authors.lastname: Zemlyachenko
authors.forename: M
authors.initials: M
authors.lastname: Hall
authors.forename: V M
authors.initials: VM
authors.lastname: Lipkin
authors.forename: K M
authors.initials: KM
authors.lastname: Boziev
mesh_terms: D000888:Antibodies, Anti-Idiotypic / Q000276:immunology; D000911:Antibodies, Monoclonal / Q000378:metabolism*; D029681:Arabidopsis Proteins; D002352:Carrier Proteins / Q000276:immunology / Q000302:isolation & purification / Q000378:metabolism*; D002843:Chromatin / Q000235:genetics; D003583:Cytokinins; D001467:Hordeum / Q000737:chemistry*; D010940:Plant Proteins; D012318:RNA Polymerase I / Q000378:metabolism*; D014158:Transcription, Genetic; D003313:Zea mays / Q000737:chemistry*
chemical_list: D000888:Antibodies, Anti-Idiotypic; D000911:Antibodies, Monoclonal; D029681:Arabidopsis Proteins; D002352:Carrier Proteins; D002843:Chromatin; D003583:Cytokinins; D010940:Plant Proteins; D012318:RNA Polymerase I