title: Bacterial assay to study plant sensor histidine kinases.
abstract: Cytokinins, like other phytohormones, act in plants as signaling molecules at very low concentrations. The system that mediates between their chemical recognition and the responses that they induce requires a hormone receptor that, together with down-stream located elements, forms a signaling network, converting the signal into a specific response. Identification of the cytokinin-binding histidine kinases CRE1/AHK4, AHK3, and AHK2 as cytokinin receptors in Arabidopsis was an important milestone in the elucidation of cytokinin signal transduction pathways. Their molecular characterization through the use of transgenic E. coli strains revealed that a variety of cytokinin compounds may have signaling functions, but only with specific receptors. This indicates that differential ligand specificities of the receptors may be a mechanism to fine-tune the various cytokinin responses. This chapter describes the detailed protocol of a method employing transgenic E. coli which substantially contributes to our understanding of cytokinin perception, a crucial step in the cytokinin regulation of diverse plant growth and development processes.
authors.affiliation: Laboratory of Growth Regulators, Institute of Experimental Botany AS CR & Palacký University, Olomouc, Czech Republic. lukas.spichal@upol.cz
authors.forename: Lukáš
authors.initials: L
authors.lastname: Spíchal
mesh_terms: D017360:Arabidopsis / Q000201:enzymology*; D029681:Arabidopsis Proteins; D001681:Biological Assay / Q000379:methods*; D003583:Cytokinins / Q000378:metabolism / Q000494:pharmacology; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D015964:Gene Expression Regulation, Bacterial / Q000187:drug effects; D000071677:Histidine Kinase; D010937:Plant Growth Regulators / Q000378:metabolism / Q000494:pharmacology; D011494:Protein Kinases / Q000235:genetics / Q000378:metabolism*; D001616:beta-Galactosidase / Q000235:genetics / Q000378:metabolism
chemical_list: D029681:Arabidopsis Proteins; D003583:Cytokinins; D010937:Plant Growth Regulators; D011494:Protein Kinases; D000071677:Histidine Kinase; C000605492:AHK2 protein, Arabidopsis; C000605493:AHK3 protein, Arabidopsis; D001616:beta-Galactosidase