Aquaporins facilitate hydrogen peroxide entry into guard cells to mediate ABA- and pathogen-triggered stomatal closure.

Autor: Rodrigues O; Biochimie et Physiologie Moléculaire des Plantes, Unité Mixte de Recherche 5004, CNRS/Institut National de la Recherche Agronomique/Montpellier SupAgro/Université de Montpellier, F-34060 Montpellier Cedex 2, France., Reshetnyak G; Biochimie et Physiologie Moléculaire des Plantes, Unité Mixte de Recherche 5004, CNRS/Institut National de la Recherche Agronomique/Montpellier SupAgro/Université de Montpellier, F-34060 Montpellier Cedex 2, France., Grondin A; Biochimie et Physiologie Moléculaire des Plantes, Unité Mixte de Recherche 5004, CNRS/Institut National de la Recherche Agronomique/Montpellier SupAgro/Université de Montpellier, F-34060 Montpellier Cedex 2, France., Saijo Y; Department of Biology, Nara Institute of Science and Technology, Ikoma, 630-0192, Japan., Leonhardt N; Laboratoire de Biologie du Développement des Plantes, French Alternative Energies and Atomic Energy Commission (CEA) Cadarache, Unité Mixte de Recherche 7265, CNRS/CEA/Aix-Marseille Université, F-13108 Saint-Paul-lez-Durance, France., Maurel C; Biochimie et Physiologie Moléculaire des Plantes, Unité Mixte de Recherche 5004, CNRS/Institut National de la Recherche Agronomique/Montpellier SupAgro/Université de Montpellier, F-34060 Montpellier Cedex 2, France., Verdoucq L; Biochimie et Physiologie Moléculaire des Plantes, Unité Mixte de Recherche 5004, CNRS/Institut National de la Recherche Agronomique/Montpellier SupAgro/Université de Montpellier, F-34060 Montpellier Cedex 2, France; lionel.verdoucq@cnrs.fr.
Jazyk: angličtina
Zdroj: Proceedings of the National Academy of Sciences of the United States of America [Proc Natl Acad Sci U S A] 2017 Aug 22; Vol. 114 (34), pp. 9200-9205. Date of Electronic Publication: 2017 Aug 07.
DOI: 10.1073/pnas.1704754114
Abstrakt: Stomatal movements are crucial for the control of plant water status and protection against pathogens. Assays on epidermal peels revealed that, similar to abscisic acid (ABA), pathogen-associated molecular pattern (PAMP) flg22 requires the At PIP2;1 aquaporin to induce stomatal closure. Flg22 also induced an increase in osmotic water permeability ( P f ) of guard cell protoplasts through activation of At PIP2;1. The use of HyPer, a genetic probe for intracellular hydrogen peroxide (H 2 O 2 ), revealed that both ABA and flg22 triggered an accumulation of H 2 O 2 in wild-type but not pip2;1 guard cells. Pretreatment of guard cells with flg22 or ABA facilitated the influx of exogenous H 2 O 2 Brassinosteroid insensitive 1-associated receptor kinase 1 (BAK1) and open stomata 1 (OST1)/Snf1-related protein kinase 2.6 (SnRK2.6) were both necessary to flg22-induced P f and both phosphorylated At PIP2;1 on Ser121 in vitro. Accumulation of H 2 O 2 and stomatal closure as induced by flg22 was restored in pip2;1 guard cells by a phosphomimetic form (Ser121Asp) but not by a phosphodeficient form (Ser121Ala) of At PIP2;1. We propose a mechanism whereby phosphorylation of At PIP2;1 Ser121 by BAK1 and/or OST1 is triggered in response to flg22 to activate its water and H 2 O 2 transport activities. This work establishes a signaling role of plasma membrane aquaporins in guard cells and potentially in other cellular context involving H 2 O 2 signaling.
Competing Interests: The authors declare no conflict of interest.
Databáze: MEDLINE
Externí odkaz: