title: Salt-Induced Tissue-Specific Cytosine Methylation Downregulates Expression of HKT Genes in Contrasting Wheat (Triticum aestivum L.) Genotypes.
abstract: Plants have evolved several strategies, including regulation of genes through epigenetic modifications, to cope with environmental stresses. DNA methylation is dynamically regulated through the methylation and demethylation of cytosine in response to environmental perturbations. High-affinity potassium transporters (HKTs) have accounted for the homeostasis of sodium and potassium ions in plants under salt stress. Wheat (Triticum aestivum L.) is sensitive to soil salinity, which impedes its growth and development, resulting in decreased productivity. The differential expression of HKTs has been reported to confer tolerance to salt stress in plants. In this study, we investigated variations in cytosine methylation and their effects on the expression of HKT genes in contrasting wheat genotypes under salt stress. We observed a genotype- and tissue-specific increase in cytosine methylation induced by NaCl stress that downregulated the expression of TaHKT2;1 and TaHKT2;3 in the shoot and root tissues of Kharchia-65, thereby contributing to its improved salt-tolerance ability. Although TaHKT1;4 was expressed only in roots and was downregulated under the stress in salt-tolerant genotypes, it was not regulated through variations in cytosine methylation. Thus, understanding epigenetic regulation and the function of HKTs would enable an improvement in salt tolerance and the development of salt-tolerant crops.
authors.affiliation: Division of Biochemistry, Indian Agricultural Research Institute , New Delhi, India .
authors.forename: Suresh
authors.initials: S
authors.lastname: Kumar
authors.affiliation: Division of Biochemistry, Indian Agricultural Research Institute , New Delhi, India .
authors.forename: Ananda Sankara
authors.initials: AS
authors.lastname: Beena
authors.affiliation: Division of Biochemistry, Indian Agricultural Research Institute , New Delhi, India .
authors.forename: Monika
authors.initials: M
authors.lastname: Awana
authors.affiliation: Division of Biochemistry, Indian Agricultural Research Institute , New Delhi, India .
authors.forename: Archana
authors.initials: A
authors.lastname: Singh
mesh_terms: D027682:Cation Transport Proteins / Q000235:genetics* / Q000378:metabolism; D003596:Cytosine / Q000378:metabolism*; D019175:DNA Methylation; D015536:Down-Regulation; D018506:Gene Expression Regulation, Plant; D005838:Genotype; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism; D011188:Potassium / Q000378:metabolism; D012964:Sodium / Q000378:metabolism; D012965:Sodium Chloride / Q000633:toxicity; D014908:Triticum / Q000187:drug effects / Q000235:genetics* / Q000378:metabolism
chemical_list: D027682:Cation Transport Proteins; D010940:Plant Proteins; D012965:Sodium Chloride; D003596:Cytosine; D012964:Sodium; D011188:Potassium
keywords: DNA methylation; Triticum aestivum; epigenetics; gene regulation; salt stress