Molecular and functional characterization of glutathione reductase genes of bread wheat Triticum aestivum L

Abstract

Plant cells and tissues remain always on risk under abiotic and biotic stresses due to increased production of reactive oxygen species. Out of many components of antioxidant machinery, glutathione reductase (GR) and glutathione play important role in the protection of cell against oxidative damage. In present study, a total of seven GR genes were identified. GR has two isoforms, one is chloroplastic and the other one is cytosolic. Chloroplastic isoform consists of targeting signal peptide and cytosolic isoform have cytosolic domain. Gene structure in terms of exon/intron organization and intron-phase, and various physico-chemical properties like molecular weight and isoelectric point were also studied. To understand the structure of protein, motif, domain, and tertiary structure analyses of TaGRs were carried out. Expression analysis suggested the probable role of GR in growth and development and revealed its role in abiotic (heat, drought, combined heat drought and salt) stresses. The differential expression and co-expression of TaGR genes and enhanced GR enzyme activity suggested their roles under drought, heat, salt, and arsenic stress. Interaction of GRs with other proteins and bio-chemical compounds of the ascorbate-glutathione cycle revealed their coordinated functioning. The miRNAs and transcription factors interaction study further pointed their functions in developmental processes and stress responses. The functional characterization of TaGR2-D gene in Saccharomyces cerevisiae and Arabidopsis thaliana under different abiotic stress conditions revealed the role of GR in abiotic stress resistance. This study gives extensive and substantial information about the importance of GR in stress responses, which might be useful for further characterization of bread wheat. newline