title: Water-deficiency conditions differently modulate the methylome of roots and leaves in barley (Hordeum vulgare L.).
abstract: One of the strategies of plant adaptation to stress is the modulation of gene expression, which may result from the regulation of DNA methylation. This study attempted to characterize and compare the barley methylome of leaves and roots under water-deficiency treatment and in the subsequent rewatering phase. Our results, obtained using methylation-sensitive amplification polymorphism sequencing analysis, indicated that the overall DNA methylation level in the barley genome was high and in general stable under water-deficiency conditions. Nevertheless, numerous differentially methylated sites (DMSs) were induced by stress in the leaves and roots. Equal proportions of novel stress-induced methylation and demethylation events were observed within the genes in the leaves, but new methylations dominated in the roots. Repetitive elements preferentially underwent demethylation in the leaves and novel methylations in the roots. Importantly, rewatering and plant recovery resulted in the reversibility of the majority of stress-induced methylation events, but this process was more efficient in the leaves than in the roots. Different biological processes were enriched within the subsets of the DMSs that were identified in the genic regions of leaves and roots. We assume that the organ specificity of the methylome changes in response to water deficiency might be an important regulatory mechanism that leads to multi-level mechanisms of stress tolerance in barley.
authors.affiliation: Department of Genetics, University of Silesia in Katowice, Jagiellonska 28, 40-032 Katowice, Poland.
authors.forename: Karolina
authors.initials: K
authors.lastname: Chwialkowska
authors.affiliation: Department of Genetics, University of Silesia in Katowice, Jagiellonska 28, 40-032 Katowice, Poland.
authors.forename: Urszula
authors.initials: U
authors.lastname: Nowakowska
authors.affiliation: Department of Genetics, University of Silesia in Katowice, Jagiellonska 28, 40-032 Katowice, Poland.
authors.forename: Anna
authors.initials: A
authors.lastname: Mroziewicz
authors.affiliation: Department of Genetics, University of Silesia in Katowice, Jagiellonska 28, 40-032 Katowice, Poland.
authors.forename: Iwona
authors.initials: I
authors.lastname: Szarejko
authors.affiliation: Department of Genetics, University of Silesia in Katowice, Jagiellonska 28, 40-032 Katowice, Poland miroslaw.kwasniewski@us.edu.pl.
authors.forename: Miroslaw
authors.initials: M
authors.lastname: Kwasniewski
mesh_terms: D003596:Cytosine / Q000378:metabolism; D019175:DNA Methylation; D018744:DNA, Plant / Q000235:genetics* / Q000378:metabolism; D055864:Droughts; D018506:Gene Expression Regulation, Plant; D001467:Hordeum / Q000235:genetics* / Q000378:metabolism; D009928:Organ Specificity; D018515:Plant Leaves / Q000378:metabolism; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism; D018517:Plant Roots / Q000378:metabolism; D017422:Sequence Analysis, DNA; D013312:Stress, Physiological; D014867:Water / Q000378:metabolism*
chemical_list: D018744:DNA, Plant; D010940:Plant Proteins; D014867:Water; D003596:Cytosine
keywords: Barley; DNA methylation; drought; epigenetics; gene expression; water stress.