title: ABA is required for the accumulation of APX1 and MBF1c during a combination of water deficit and heat stress.
abstract: Abscisic acid (ABA) plays a key role in plant acclimation to abiotic stress. Although recent studies suggested that ABA could also be important for plant acclimation to a combination of abiotic stresses, its role in this response is currently unknown. Here we studied the response of mutants impaired in ABA signalling (abi1-1) and biosynthesis (aba1-1) to a combination of water deficit and heat stress. Both mutants displayed reduced growth, biomass, and survival when subjected to stress combination. Focusing on abi1-1, we found that although its stomata had an impaired response to water deficit, remaining significantly more open than wild type, its stomatal aperture was surprisingly reduced when subjected to the stress combination. Stomatal closure during stress combination in abi1-1 was accompanied by higher levels of H2O2in leaves, suggesting that H2O2might play a role in this response. In contrast to the almost wild-type stomatal closure phenotype of abi1-1 during stress combination, the accumulation of ascorbate peroxidase 1 and multiprotein bridging factor 1c proteins, required for acclimation to a combination of water deficit and heat stress, was significantly reduced in abi1-1 Our findings reveal a key function for ABA in regulating the accumulation of essential proteins during a combination of water deficit and heat stress.
authors: Departamento de Ciencias Agrarias y del Medio Natural, Universitat Jaume I, Campus Riu Sec, E- 12071 Castello de la Plana, Spain.
authors: Sara I
authors: SI
authors: Zandalinas
authors: Departamento de Ciencias Agrarias y del Medio Natural, Universitat Jaume I, Campus Riu Sec, E- 12071 Castello de la Plana, Spain.
authors: Damián
authors: D
authors: Balfagón
authors: Departamento de Ciencias Agrarias y del Medio Natural, Universitat Jaume I, Campus Riu Sec, E- 12071 Castello de la Plana, Spain.
authors: Vicent
authors: V
authors: Arbona
authors: Departamento de Ciencias Agrarias y del Medio Natural, Universitat Jaume I, Campus Riu Sec, E- 12071 Castello de la Plana, Spain.
authors: Aurelio
authors: A
authors: Gómez-Cadenas
authors: Department of Biological Sciences, College of Arts and Sciences, University of North Texas, 1155 Union Circle #305220, Denton, TX 76203-5017, USA.
authors: Madhuri A
authors: MA
authors: Inupakutika
authors: Department of Biological Sciences, College of Arts and Sciences, University of North Texas, 1155 Union Circle #305220, Denton, TX 76203-5017, USA ron.mittler@unt.edu.
authors: Ron
authors: R
authors: Mittler
mesh_terms: D000040:Abscisic Acid / Q000378:metabolism*; D017360:Arabidopsis / Q000378:metabolism / Q000502:physiology; D029681:Arabidopsis Proteins / Q000378:metabolism / Q000502:physiology*; D060387:Ascorbate Peroxidases / Q000378:metabolism / Q000502:physiology*; D003681:Dehydration / Q000378:metabolism / Q000503:physiopathology; D006358:Hot Temperature / Q000009:adverse effects; D010937:Plant Growth Regulators / Q000502:physiology*; D054046:Plant Stomata / Q000502:physiology; D013312:Stress, Physiological / Q000502:physiology; D015534:Trans-Activators / Q000378:metabolism / Q000502:physiology*
chemical_list: D029681:Arabidopsis Proteins; C491466:MBF1 protein, Arabidopsis; D010937:Plant Growth Regulators; D015534:Trans-Activators; D000040:Abscisic Acid; C555290:APX1 protein, Arabidopsis; D060387:Ascorbate Peroxidases
keywords: 
  aba1-1
  ; 
  abi1-1
  ; APX1; MBF1c; abiotic stress; abscisic acid; acclimation; heat stress; stomata; stress combination; water deficit.