Differential regulation of aquaporins, small GTPases and V-ATPases proteins in rice leaves subjected to drought stress and recovery

• Published in: Proteomics (Weinheim) Vol. 12; no. 6; pp. 864 - 877
• Main Authors: Mirzaei, Mehdi, Pascovici, Dana, Atwell, Brian J., Haynes, Paul A.
• Format: Journal Article
• Language: English
• Published: Weinheim Blackwell Publishing Ltd 01-03-2012; Wiley-VCH; Wiley Subscription Services, Inc
• Subjects: Analytical, structural and metabolic biochemistry; Aquaporins; Aquaporins - genetics; Aquaporins - metabolism; Biological and medical sciences; Drought; Droughts; Fundamental and applied biological sciences. Psychology; Gene expression; Gene Expression Regulation, Plant; Heat-Shock Proteins, Small - genetics; Heat-Shock Proteins, Small - metabolism; Label-free shotgun proteomics; Miscellaneous; Monomeric GTP-Binding Proteins - genetics; Monomeric GTP-Binding Proteins - metabolism; Oryza - genetics; Oryza - metabolism; Oryza sativa; Plant Leaves - genetics; Plant Leaves - metabolism; Plant Proteins - genetics; Plant Proteins - metabolism; Plant proteomics; Proteins; Proteomics; Rice; Seedlings - genetics; Seedlings - metabolism; Small GTPases; Vacuolar Proton-Translocating ATPases - genetics; Vacuolar Proton-Translocating ATPases - metabolism; Monocotyledones; Enzyme; Triphosphoric monoester hydrolases; Aquaporins; Adenosinetriphosphatase; Small GTPases; dGTPase; Esterases; Label-free shotgun proteomics; Protein; Stress; Oryza sativa; Gramineae; Angiospermae; Proteomics; Plant proteomics; Hydrolases; Spermatophyta; Drought; Rice
• ISSN: 1615-9853; 1615-9861
• DOI: 10.1002/pmic.201100389

Mechanisms of drought tolerance are complex, interacting, and polygenic. This paper describes patterns of gene expression at precise physiological stages of drought in 35‐day‐old seedlings of Oryza sativa cv. Nipponbare. Drought was imposed gradually for up to 15 days, causing abscisic acid levels to rise and growth to cease, and plants were then re‐watered. Proteins were identified from leaf samples after moderate drought, extreme drought, and 3 and 6 days of re‐watering. Label‐free quantitative shotgun proteomics resulted in identification of 1548 non‐redundant proteins. More proteins were down‐regulated in early stages of drought but more were up‐regulated as severe drought developed. After re‐watering, there was notable down regulation, suggesting that stress‐related proteins were being degraded. Proteins involved in signalling and transport became dominant as severe drought took hold but decreased again on re‐watering. Most of the nine aquaporins identified were responsive to drought, with six decreasing rapidly in abundance as plants were re‐watered. Nine G‐proteins appeared in large amounts during severe drought and dramatically degraded once plants were re‐watered. We speculate that water transport and drought signalling are critical elements of the overall response to drought in rice and might be the key to biotechnological approaches to drought tolerance.