Promoter and expression studies on an Arabidopsis thaliana dehydrin gene

A genomic clone of a group 2 lea/rab/dehydrin gene from Arabidopsis thaliana, Xero2/lti30, was cloned and sequenced. Promoter-GUS fusions were introduced into plants to analyse the promoter and determine expression patterns. Using root cultures, GUS expression was found to be moderately stimulated by abscisic acid (ABA), wounding, cold and dehydration. Results with an ABA-deficient mutant suggested endogenous ABA is required for these responses. Promoter deletion studies indicated multiple cis-acting elements are involved in the induction of the gene. GUS expression occurred in desiccated seeds, in all tissues of young seedlings and in roots (with the exception of the root tip), desiccated pollen grains, trichomes and the vascular tissues of leaves and stems in mature plants.