Overexpression of the Trehalase Gene AtTRE1 Leads to Increased Drought Stress Tolerance in Arabidopsis and Is Involved in Abscisic Acid-Induced Stomatal Closure

• Published in: Plant physiology (Bethesda) Vol. 161; no. 3; pp. 1158 - 1171
• Main Authors: Van Houtte, Hilde, Vandesteene, Lies, López-Galvis, Lorena, Lemmens, Liesbeth, Kissel, Ewaut, Carpentier, Sebastien, Feil, Regina, Avonce, Nelson, Beeckman, Tom, Lunn, John E., Van Dijck, Patrick
• Format: Journal Article
• Language: English
• Published: Rockville, MD American Society of Plant Biologists 01-03-2013
• Subjects: Abscisic Acid - pharmacology; Adaptation, Physiological - drug effects; Arabidopsis - drug effects; Arabidopsis - enzymology; Arabidopsis - genetics; Arabidopsis - physiology; Arabidopsis Proteins - genetics; Arabidopsis Proteins - metabolism; BIOCHEMISTRY AND METABOLISM; Biological and medical sciences; Dehydration; Drought; Droughts; Fundamental and applied biological sciences. Psychology; Gene Expression Regulation, Plant - drug effects; Glucuronidase - metabolism; Guard cells; Leaves; Movement - drug effects; Plant growth; Plant physiology and development; Plant Stomata - drug effects; Plant Stomata - genetics; Plant Stomata - physiology; Plant Transpiration - drug effects; Plant Transpiration - genetics; Plants; Plants, Genetically Modified; Seedlings; Seedlings - drug effects; Seedlings - physiology; Stress tolerance; Stress, Physiological - drug effects; Stress, Physiological - genetics; Temperature; Transgenic plants; Trehalase - genetics; Trehalase - metabolism; Water loss; Yeasts; Enzyme; Stomatal conductance; Gene overexpression; Tolerance; Water stress; Glycosylases; Arabidopsis thaliana; Gene; Plant physiology; Cruciferae; α,α-Trehalase; Dicotyledones; Glycosidases; Sesquiterpenes; Angiospermae; Stomatal movement; Abscisic acid; Hydrolases; Plant growth substance; Spermatophyta; Experimental plant; Drought
• ISSN: 0032-0889; 1532-2548; 1532-2548
• DOI: 10.1104/pp.112.211391

Introduction of microbial trehalose biosynthesis enzymes has been reported to enhance abiotic stress resistance in plants but also resulted in undesirable traits. Here, we present an approach for engineering drought stress tolerance by modifying the endogenous trehalase activity in Arabidopsis (Arabidopsis thaliana). AtTRE1 encodes the Arabidopsis trehalase, the only enzyme known in this species to specifically hydrolyze trehalose into glucose. AtTRE1-overexpressing and Attre1 mutant lines were constructed and tested for their performance in drought stress assays. AtTRE1-overexpressing plants had decreased trehalose levels and recovered better after drought stress, whereas Attre1 mutants had elevated trehalose contents and exhibited a drought-susceptible phenotype. Leaf detachment assays showed that Attre1 mutants lose water faster than wild-type plants, whereas AtTRE1-overexpressing plants have a better water-retaining capacity. In vitro studies revealed that abscisic acidmediated closure of stomata is impaired in Attre1 lines, whereas the AtTRE1 overexpressors are more sensitive toward abscisic acid-dependent stomatal closure. This observation is further supported by the altered leaf temperatures seen in trehalase-modified plantlets during in vivo drought stress studies. Our results show that overexpression of plant trehalase improves drought stress tolerance in Arabidopsis and that trehalase plays a role in the regulation of stomatal closure in the plant drought stress response.