Characterization of a glutathione S-transferase gene arranged in tandem with the ATGST1 gene in Arabidopsis thaliana

A novel glutathione S-transferase gene, designated ATGST11, is tandemly arr anged with the ATGST1 gene which is known to be regulated by various enviro nmental stresses in the Arabidopsis genome. The ATGST11 gene structure is v ery similar to the ATGST1 gene with complete conservation of intron positio n and with a highly conserved nucleotide sequence, suggesting that they lik ely arose by duplication of a single primordial gene. The ATGST11 gene cont ains the entire transcriptional unit in 3 exons interrupted by two introns, which predicts a GST of 209 amino acids. The gene is proven to be constitu tively transcribed at a very low level in root, stem, leaf and flower. Cis elements of the gene promoter, possibly responsible for the transcriptional regulation, may be mutated, and this suggests that gene transcription is n ot induced by environmental stimuli.