Abstract：Glutathione reductase (GR) is one of the key enzymes in the plant antioxidant system. In this study, a full-length cDNA sequence designated as BnGR1 was cloned by RACE methods based on the relative unigene sequence in ramie (Boehmeria nivea (L.) Gaud.) transcriptome sequencing. The full-length cDNA sequence (GenBank accession: KF747758) of BnGR1 was 1 977, and the ORF was 1 494 bp, which encoded 497 amino acids with predicted pI of 5.68 and molecule weight of 53.7 kD, respectively. BnGR1 contained a pyridine nucleotide-disulphide oxidoreductases classⅠ active site, a nicotinamide adenine dinucleotide phosphate (NADP) binding site, a flavin adenine dinucletide (FAD) binding site, two L-glutathione oxidized (GSSG) binding sites and a special structure domain of cytosolic GR, respectively. Homology comparison analysis showed that the deduced BnGR1 amino acid sequence shared a 88% homology with GR gene (EOY05332) in cocoa (Theobroma cacao). Prokaryotic expression vector pGEX-4T-BnGR1 was established and transformed into Escherichia coli BL21 after isopropyl-β-d-thiogalactoside (IPTG) induction, which showed a successful gene expression. The expression pattern analysis carried out by quantitative Real-time PCR indicated that BnGR1 expressed in root, stem, stem apex and leaves, with the highest expression level in mature leaves and the lowest in stem. The BnGR1 gene was up-regulated by CdCl2, abscisic acid (ABA) and salicylic acid (SA) treatments. The results indicated that BnGR1 gene might play an important role in response to abiotic stresses of ramie， which provide the basic data for exploring the ramie resistance molecular mechanism of heavy metals Cd2+.
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