title: Transgenic barley overexpressing a cytokinin dehydrogenase gene shows greater tolerance to drought stress.
abstract: Together with auxins, cytokinins are the main plant hormones involved in many different physiological processes. Given this knowledge, cytokinin levels can be manipulated by genetic modification in order to improve agronomic parameters of cereals in relation to, for example, morphology, yield, and tolerance to various stresses. The barley (Hordeum vulgare) cultivar Golden Promise was transformed using the cytokinin dehydrogenase 1 gene from Arabidopsis thaliana (AtCKX1) under the control of mild root-specific β-glucosidase promoter from maize. Increased cytokinin degradation activity was observed positively to affect the number and length of lateral roots. The impact on morphology depended upon the recombinant protein's subcellular compartmentation. While assumed cytosolic and vacuolar targeting of AtCKX1 had negligible effect on shoot growth, secretion of AtCKX1 protein to the apoplast had a negative effect on development of the aerial part and yield. Upon the application of severe drought stress, all transgenic genotypes maintained higher water content and showed better growth and yield parameters during revitalization. Higher tolerance to drought stress was most caused by altered root morphology resulting in better dehydration avoidance.
authors.affiliation: Department of Molecular Biology, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University in Olomouc, Šlechtitelů 27, 783 71 Olomouc, Czech Republic.
authors.forename: Hana
authors.initials: H
authors.lastname: Pospíšilová
authors.affiliation: Department of Molecular Biology, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University in Olomouc, Šlechtitelů 27, 783 71 Olomouc, Czech Republic.
authors.forename: Eva
authors.initials: E
authors.lastname: Jiskrová
authors.affiliation: Department of Molecular Biology, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University in Olomouc, Šlechtitelů 27, 783 71 Olomouc, Czech Republic; Institute of Molecular and Translational Medicine, Faculty of Medicine and Dentistry, Palacký University Olomouc, Hněvotínská 1333/5, 779 00 Olomouc, Czech Republic.
authors.forename: Petr
authors.initials: P
authors.lastname: Vojta
authors.affiliation: Department of Molecular Biology, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University in Olomouc, Šlechtitelů 27, 783 71 Olomouc, Czech Republic.
authors.forename: Katarína
authors.initials: K
authors.lastname: Mrízová
authors.affiliation: Department of Molecular Biology, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University in Olomouc, Šlechtitelů 27, 783 71 Olomouc, Czech Republic.
authors.forename: Filip
authors.initials: F
authors.lastname: Kokáš
authors.affiliation: Department of Molecular Biology, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University in Olomouc, Šlechtitelů 27, 783 71 Olomouc, Czech Republic.
authors.forename: Mária Majeská
authors.initials: MM
authors.lastname: Čudejková
authors.affiliation: Department of Molecular Biology, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University in Olomouc, Šlechtitelů 27, 783 71 Olomouc, Czech Republic.
authors.forename: Veronique
authors.initials: V
authors.lastname: Bergougnoux
authors.affiliation: Department of Molecular Biology, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University in Olomouc, Šlechtitelů 27, 783 71 Olomouc, Czech Republic.
authors.forename: Ondřej
authors.initials: O
authors.lastname: Plíhal
authors.affiliation: Department of Crop Science, Mendel University in Brno, Zemědělská 1, 613 00 Brno, Czech Republic.
authors.forename: Jana
authors.initials: J
authors.lastname: Klimešová
authors.affiliation: Department of Metabolomics, Centre of the Region Haná for Biotechnological and Agricultural Research, Institute of Experimental Botany AS CR, Šlechtitelů 27, 783 71 Olomouc, Czech Republic.
authors.forename: Ondřej
authors.initials: O
authors.lastname: Novák
authors.affiliation: Department of Molecular Biology, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University in Olomouc, Šlechtitelů 27, 783 71 Olomouc, Czech Republic.
authors.forename: Lenka
authors.initials: L
authors.lastname: Dzurová
authors.affiliation: Department of Molecular Biology, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University in Olomouc, Šlechtitelů 27, 783 71 Olomouc, Czech Republic.
authors.forename: Ivo
authors.initials: I
authors.lastname: Frébort
authors.affiliation: Department of Molecular Biology, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University in Olomouc, Šlechtitelů 27, 783 71 Olomouc, Czech Republic. Electronic address: petr.galuszka@upol.cz.
authors.forename: Petr
authors.initials: P
authors.lastname: Galuszka
mesh_terms: D000064:Acclimatization / Q000235:genetics / Q000502:physiology; D029681:Arabidopsis Proteins / Q000235:genetics / Q000502:physiology; D001709:Biotechnology; D003583:Cytokinins / Q000235:genetics / Q000378:metabolism; D055864:Droughts; D020869:Gene Expression Profiling; D017343:Genes, Plant; D001467:Hordeum / Q000235:genetics* / Q000254:growth & development / Q000502:physiology*; D053858:Metabolic Networks and Pathways; D010088:Oxidoreductases / Q000235:genetics*; D010641:Phenotype; D010937:Plant Growth Regulators / Q000235:genetics / Q000378:metabolism; D010940:Plant Proteins / Q000235:genetics*; D018517:Plant Roots / Q000502:physiology; D030821:Plants, Genetically Modified; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D013312:Stress, Physiological; D015854:Up-Regulation
chemical_list: D029681:Arabidopsis Proteins; D003583:Cytokinins; D010937:Plant Growth Regulators; D010940:Plant Proteins; D011994:Recombinant Proteins; D010088:Oxidoreductases; C019984:cytokinin oxidase