title: The homeodomain transcription factor TaHDZipI-2 from wheat regulates frost tolerance, flowering time and spike development in transgenic barley.
abstract: Homeodomain leucine zipper class I (HD-Zip I) transcription factors (TFs) play key roles in the regulation of plant growth and development under stresses. Functions of the TaHDZipI-2 gene isolated from the endosperm of developing wheat grain were revealed. Molecular characterization of TaHDZipI-2 protein included studies of its dimerisation, protein-DNA interactions and gene activation properties using pull-down assays, in-yeast methods and transient expression assays in wheat cells. The analysis of TaHDZipI-2 gene functions was performed using transgenic barley plants. It included comparison of developmental phenotypes, yield components, grain quality, frost tolerance and the levels of expression of potential target genes in transgenic and control plants. Transgenic TaHDZipI-2 lines showed characteristic phenotypic features that included reduced growth rates, reduced biomass, early flowering, light-coloured leaves and narrowly elongated spikes. Transgenic lines produced 25-40% more seeds per spike than control plants, but with 50-60% smaller grain size. In vivo lipid imaging exposed changes in the distribution of lipids between the embryo and endosperm in transgenic seeds. Transgenic lines were significantly more tolerant to frost than control plants. Our data suggest the role of TaHDZipI-2 in controlling several key processes underlying frost tolerance, transition to flowering and spike development.
authors.affiliation: Australian Centre for Plant Functional Genomics, School of Agriculture, Food and Wine, University of Adelaide, Waite Campus, Glen Osmond, SA, 5064, Australia.
authors.forename: Nataliya
authors.initials: N
authors.lastname: Kovalchuk
authors.affiliation: Australian Centre for Plant Functional Genomics, School of Agriculture, Food and Wine, University of Adelaide, Waite Campus, Glen Osmond, SA, 5064, Australia.
authors.forename: William
authors.initials: W
authors.lastname: Chew
authors.affiliation: Australian Centre for Plant Functional Genomics, School of Agriculture, Food and Wine, University of Adelaide, Waite Campus, Glen Osmond, SA, 5064, Australia.
authors.forename: Pradeep
authors.initials: P
authors.lastname: Sornaraj
authors.affiliation: Australian Centre for Plant Functional Genomics, School of Agriculture, Food and Wine, University of Adelaide, Waite Campus, Glen Osmond, SA, 5064, Australia.
authors.forename: Nikolai
authors.initials: N
authors.lastname: Borisjuk
authors.affiliation: Australian Centre for Plant Functional Genomics, School of Agriculture, Food and Wine, University of Adelaide, Waite Campus, Glen Osmond, SA, 5064, Australia.
authors.forename: Nannan
authors.initials: N
authors.lastname: Yang
authors.affiliation: Australian Research Council Centre of Excellence in Plant Cell Walls, School of Agriculture, Food and Wine, University of Adelaide, Waite Campus, Glen Osmond, SA, 5064, Australia.
authors.forename: Rohan
authors.initials: R
authors.lastname: Singh
authors.affiliation: Australian Centre for Plant Functional Genomics, School of Agriculture, Food and Wine, University of Adelaide, Waite Campus, Glen Osmond, SA, 5064, Australia.
authors.forename: Natalia
authors.initials: N
authors.lastname: Bazanova
authors.affiliation: Australian Centre for Plant Functional Genomics, School of Agriculture, Food and Wine, University of Adelaide, Waite Campus, Glen Osmond, SA, 5064, Australia.
authors.forename: Yuri
authors.initials: Y
authors.lastname: Shavrukov
authors.affiliation: Department of Molecular Genetics, Leibniz Institute of Plant Genetics and Crop Plant Research, D-06466, Gatersleben, Germany.
authors.forename: Andre
authors.initials: A
authors.lastname: Guendel
authors.affiliation: Department of Molecular Genetics, Leibniz Institute of Plant Genetics and Crop Plant Research, D-06466, Gatersleben, Germany.
authors.forename: Eberhard
authors.initials: E
authors.lastname: Munz
authors.affiliation: Department of Molecular Genetics, Leibniz Institute of Plant Genetics and Crop Plant Research, D-06466, Gatersleben, Germany.
authors.forename: Ljudmilla
authors.initials: L
authors.lastname: Borisjuk
authors.affiliation: Australian Centre for Plant Functional Genomics, School of Agriculture, Food and Wine, University of Adelaide, Waite Campus, Glen Osmond, SA, 5064, Australia.
authors.forename: Peter
authors.initials: P
authors.lastname: Langridge
authors.affiliation: Australian Centre for Plant Functional Genomics, School of Agriculture, Food and Wine, University of Adelaide, Waite Campus, Glen Osmond, SA, 5064, Australia.
authors.forename: Maria
authors.initials: M
authors.lastname: Hrmova
authors.affiliation: Australian Centre for Plant Functional Genomics, School of Agriculture, Food and Wine, University of Adelaide, Waite Campus, Glen Osmond, SA, 5064, Australia.
authors.forename: Sergiy
authors.initials: S
authors.lastname: Lopato
mesh_terms: D000222:Adaptation, Physiological; D035264:Flowers / Q000502:physiology; D005615:Freezing; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant; D018398:Homeodomain Proteins / Q000378:metabolism*; D001467:Hordeum / Q000033:anatomy & histology / Q000235:genetics* / Q000254:growth & development / Q000502:physiology*; D016350:Leucine Zippers; D008055:Lipids / Q000032:analysis; D010641:Phenotype; D010802:Phylogeny; D010940:Plant Proteins / Q000378:metabolism*; D030821:Plants, Genetically Modified; D011401:Promoter Regions, Genetic; D055503:Protein Multimerization; D036226:Seedlings / Q000502:physiology; D012639:Seeds / Q000033:anatomy & histology / Q000502:physiology; D014157:Transcription Factors / Q000378:metabolism*; D015533:Transcriptional Activation / Q000235:genetics; D019076:Transgenes
chemical_list: D018398:Homeodomain Proteins; D008055:Lipids; D010940:Plant Proteins; D014157:Transcription Factors
keywords: barley; flowering time; frost tolerance; growth and development regulation; homeodomain leucine zipper class I (HD-Zip I); vernalisation