Abstract：Glutathione transferase (PsGSTU1) gene was isolated by RACE from Polygonum sibiricum Laxm, the PsGSTU1 gene had a complete open reading frame of 669 bp and encoded a peptide of 222 amino acid residues. Based on the comparison with other amino acids sequences among glutathione transferase family and the analysis of the phylogenetic evolution, this PsGSTU1 belonged to a glutathione transferase Tau kind of family. Expression analysis by RT-PCR showed that PsGSTU1 gene expressed in leaf, stem and root, especially higher expression in stems, next was leaf and root. After 3% NaHCO3 stress, this PsGSTU1 gene’s largest expression amount appeared at 48 h in leaf and root, but the largest expression within stem appeared at 72 h, When the stress was removed, the PsGSTU1 gene’s expression amount change within various organs were found as follows: root>leaf>stem. Subsequently, PsGSTU1 gene that had a complete cDNA was inserted into the pET28a plasmid to construct the prokaryotic vector and then transformed into Escherichia coli. The 26 kD protein was expressed after inducing by IPTG, and the resistance of E. coli expressed protein to NaHCO3 got enhanced remarkably.
