title: Functional analysis of the new barley gene HvKu80 indicates that it plays a key role in double-strand DNA break repair and telomere length regulation.
abstract: Genotoxic stress causes a reduced stability of the plant genome and has a detrimental effect on plant growth and productivity. Double-strand breaks (DSBs) are the most harmful of all DNA lesions because they cause the loss of genetic information on both strands of the DNA helix. In the presented study the coding and genomic sequences of the HvKu80 gene were determined. A mutational analysis of two fragments of HvKu80 using TILLING (Targeting Induced Local Lesions IN Genomes) allowed 12 mutations to be detected, which resulted in identification of 11 alleles. Multidirectional analyses demonstrated that the HvKu80 gene is involved in the elimination of DSBs in Hordeum vulgare. The barley mutants carrying the identified ku80.c and ku80.j alleles accumulated bleomycin-induced DSBs to a much greater extent than the parent cultivar 'Sebastian'. The altered reaction of the mutants to DSB-inducing agent and the kinetics of DNA repair in these genotypes are associated with a lower expression level of the mutated gene. The study also demonstrated the significant role of the HvKu80 gene in the regulation of telomere length in barley.
authors.forename: Magdalena
authors.initials: M
authors.lastname: Stolarek
authors.forename: Damian
authors.initials: D
authors.lastname: Gruszka
authors.affiliation: Department of Plant Anatomy and Cytology, Faculty of Biology and Environment Protection, University of Silesia, Jagiellonska 28, Katowice 40-032, Poland.
authors.forename: Agnieszka
authors.initials: A
authors.lastname: Braszewska-Zalewska
authors.forename: Mirosław
authors.initials: M
authors.lastname: Maluszynski
mesh_terms: D000483:Alleles; D000595:Amino Acid Sequence; D053903:DNA Breaks, Double-Stranded; D004265:DNA Helicases / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D004252:DNA Mutational Analysis; D004260:DNA Repair; D018506:Gene Expression Regulation, Plant; D023061:Gene Order; D017343:Genes, Plant; D056084:Genetic Fitness; D006720:Homozygote; D001467:Hordeum / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D008969:Molecular Sequence Data; D009154:Mutation; D016366:Open Reading Frames; D016415:Sequence Alignment; D059505:Telomere Homeostasis / Q000235:genetics*
chemical_list: D004265:DNA Helicases