Under drought stress, the stress hormone ABA addresses the SnR kinase OST1 via its cytosolic receptor and the protein phosphatase ABI1. Upon activation, OST1 phosphorylates the guard cell S-type anion channel SLAC1. Arabidopsis ABI1 and OST1 loss-of-function mutants are characterized by an extreme wilting 'open stomata' phenotype. Given the fact that guard cells express both SLAC- and R-/QUAC-type anion channels, we questioned whether OST1, besides SLAC1, also controls the QUAC1 channel. In other words, are ABI1/OST1 defects preventing both of the guard cell anion channel types from operating properly in terms of stomatal closure? The activation of the R-/QUAC-type anion channel by ABA signaling kinase OST1 and phosphatase ABI1 was analyzed in two experimental systems: Arabidopsis guard cells and the plant cell-free background of Xenopus oocytes. Patch-clamp studies on guard cells show that ABA activates R-/QUAC-type currents of wild-type plants, but to a much lesser extent in those of abi1-1 and ost1-2 mutants. In the oocyte system the co-expression of QUAC1 and OST1 resulted in a pronounced activation of the R-type anion channel. These studies indicate that OST1 is addressing both S-/SLAC- and R-/QUAC-type guard cell anion channels, and explain why the ost1-2 mutant is much more sensitive to drought than single slac1 or quac1 mutants.
Description
Open stomata 1 (OST1) kinase controls R-type anion channel QUAC1 in Arabidopsis guard cells - PubMed
%0 Journal Article
%1 imes2013stomata
%A Imes, Dennis
%A Mumm, Patrick
%A Böhm, Jennifer
%A Al-Rasheid, Khaled A S
%A Marten, Irene
%A Geiger, Dietmar
%A Hedrich, Rainer
%C England
%D 2013
%J The Plant journal : for cell and molecular biology
%K imported
%N 3
%P 372--382
%R 10.1111/tpj.12133
%T Open stomata 1 (OST1) kinase controls R-type anion channel QUAC1 in Arabidopsis guard cells
%U https://pubmed.ncbi.nlm.nih.gov/23452338
%V 74
%X Under drought stress, the stress hormone ABA addresses the SnR kinase OST1 via its cytosolic receptor and the protein phosphatase ABI1. Upon activation, OST1 phosphorylates the guard cell S-type anion channel SLAC1. Arabidopsis ABI1 and OST1 loss-of-function mutants are characterized by an extreme wilting 'open stomata' phenotype. Given the fact that guard cells express both SLAC- and R-/QUAC-type anion channels, we questioned whether OST1, besides SLAC1, also controls the QUAC1 channel. In other words, are ABI1/OST1 defects preventing both of the guard cell anion channel types from operating properly in terms of stomatal closure? The activation of the R-/QUAC-type anion channel by ABA signaling kinase OST1 and phosphatase ABI1 was analyzed in two experimental systems: Arabidopsis guard cells and the plant cell-free background of Xenopus oocytes. Patch-clamp studies on guard cells show that ABA activates R-/QUAC-type currents of wild-type plants, but to a much lesser extent in those of abi1-1 and ost1-2 mutants. In the oocyte system the co-expression of QUAC1 and OST1 resulted in a pronounced activation of the R-type anion channel. These studies indicate that OST1 is addressing both S-/SLAC- and R-/QUAC-type guard cell anion channels, and explain why the ost1-2 mutant is much more sensitive to drought than single slac1 or quac1 mutants.
@article{imes2013stomata,
abstract = {Under drought stress, the stress hormone ABA addresses the SnR kinase OST1 via its cytosolic receptor and the protein phosphatase ABI1. Upon activation, OST1 phosphorylates the guard cell S-type anion channel SLAC1. Arabidopsis ABI1 and OST1 loss-of-function mutants are characterized by an extreme wilting 'open stomata' phenotype. Given the fact that guard cells express both SLAC- and R-/QUAC-type anion channels, we questioned whether OST1, besides SLAC1, also controls the QUAC1 channel. In other words, are ABI1/OST1 defects preventing both of the guard cell anion channel types from operating properly in terms of stomatal closure? The activation of the R-/QUAC-type anion channel by ABA signaling kinase OST1 and phosphatase ABI1 was analyzed in two experimental systems: Arabidopsis guard cells and the plant cell-free background of Xenopus oocytes. Patch-clamp studies on guard cells show that ABA activates R-/QUAC-type currents of wild-type plants, but to a much lesser extent in those of abi1-1 and ost1-2 mutants. In the oocyte system the co-expression of QUAC1 and OST1 resulted in a pronounced activation of the R-type anion channel. These studies indicate that OST1 is addressing both S-/SLAC- and R-/QUAC-type guard cell anion channels, and explain why the ost1-2 mutant is much more sensitive to drought than single slac1 or quac1 mutants.},
added-at = {2024-02-16T13:34:01.000+0100},
address = {England},
author = {Imes, Dennis and Mumm, Patrick and Böhm, Jennifer and Al-Rasheid, Khaled A S and Marten, Irene and Geiger, Dietmar and Hedrich, Rainer},
biburl = {https://www.bibsonomy.org/bibtex/21583dcaa57b319c9f39310e41e59c58c/imarten},
comment = {23452338[pmid]},
description = {Open stomata 1 (OST1) kinase controls R-type anion channel QUAC1 in Arabidopsis guard cells - PubMed},
doi = {10.1111/tpj.12133},
interhash = {beccb1d4a847dc84f08e96ccb6c6733d},
intrahash = {1583dcaa57b319c9f39310e41e59c58c},
issn = {1365313X},
journal = {The Plant journal : for cell and molecular biology},
keywords = {imported},
month = may,
number = 3,
pages = {372--382},
timestamp = {2024-02-16T13:34:01.000+0100},
title = {Open stomata 1 (OST1) kinase controls R-type anion channel QUAC1 in Arabidopsis guard cells},
url = {https://pubmed.ncbi.nlm.nih.gov/23452338},
volume = 74,
year = 2013
}