Overexpression of Isoprene Synthase Affects ABA- and Drought-Related Gene Expression and Enhances Tolerance to Abiotic Stress

• Published in: International journal of molecular sciences Vol. 21; no. 12; p. 4276
• Main Authors: Xu, Jia, Trainotti, Livio, Li, Mingai, Varotto, Claudio
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 16.06.2020; MDPI
• Subjects: Abiotic stress; Abscisic acid; abscisic acid (ABA); Abscisic Acid - pharmacology; Alkyl and Aryl Transferases - genetics; Alkyl and Aryl Transferases - metabolism; Arabidopsis - genetics; Arabidopsis - growth & development; Arabidopsis Proteins - genetics; Atmospheric chemistry; Biosynthesis; Butadienes - pharmacology; Cold Shock Proteins and Peptides - genetics; Deprivation; Drought; Droughts; Enzymes; Gene expression; Gene Expression Regulation, Plant - drug effects; gene transcription; Genotype & phenotype; Glutamate-5-Semialdehyde Dehydrogenase - genetics; Hemiterpenes - pharmacology; Impact resistance; Isoprene; isoprene synthase; Multienzyme Complexes - genetics; Organ Specificity; Osmotic stress; Phosphotransferases (Alcohol Group Acceptor) - genetics; Physiology; Plant Proteins - genetics; Plant Proteins - metabolism; Plants, Genetically Modified - growth & development; Seeds; Signal transduction; Signal Transduction - drug effects; Stomata; Stress, Physiological; Studies; Tobacco; transgenic arabidopsis; Transgenic plants; Volatile compounds; water limitation stress; water limitation stress; abscisic acid (ABA); isoprene synthase; gene transcription; isoprene; transgenic arabidopsis
• DOI: 10.3390/ijms21124276
• ISSN: 1422-0067; 1661-6596

Isoprene is the most abundant single biogenic volatile compound emitted by plants. Despite the relevance of this molecule to plant abiotic resistance and its impact on global atmospheric chemistry, little is known about the details of its mechanism of action. Here, we characterized through both physiological and molecular methods the mechanisms of action of isoprene using model transgenic arabidopsis lines overexpressing a monocot isoprene synthase gene. Our results demonstrated the effect that isoprene had on ABA signaling at different tissue-specific, spatial, and temporal scales. In particular, we found that isoprene enhanced stomatal sensitivity to ABA through upregulation of signaling gene. By contrast, isoprene decreased sensitivity to ABA in germinating seeds and roots, suggesting tissue-specific mechanisms of action. In leaves, isoprene caused the downregulation of and genes, suggesting that the enhanced tolerance to water-deprivation stress observed in isoprene-emitting plants may be mediated chiefly by an enhanced membrane integrity and tolerance to osmotic stress.