%0 Journal Article
%A Liina Jakobson
%A Lauri Vaahtera
%A Kadri Tõldsepp
%A Maris Nuhkat
%A Cun Wang
%A Yuh-Shuh Wang
%A Hanna Hõrak
%A Ervin Valk
%A Priit Pechter
%A Yana Sindarovska
%A Jing Tang
%A Chuanlei Xiao
%A Yang Xu
%A Ulvi Gerst Talas
%A Maido Remm
%A Saijaliisa Kangasjärvi
%A M. Rob G. Roelfsema
%A Honghong Hu
%A Jaakko Kangasjärvi
%A Mart Loog
%A Julian I. Schroeder
%A Hannes Kollist
%A Mikael Brosché
%T Natural Variation in Arabidopsis Cvi-0 Accession Uncovers Regulation of Guard Cell CO2 Signaling by MPK12
%D 2016
%R 10.1101/073015
%J bioRxiv
%P 073015
%X Plant gas exchange is regulated by guard cells that form stomatal pores. Stomatal adjustments are crucial for plant survival; they regulate uptake of CO2 for photosynthesis, loss of water and entrance of air pollutants such as ozone. We mapped ozone hypersensitivity, more open stomata and stomatal CO2-insensitivity phenotypes of the Arabidopsis thaliana accession Cvi-0 to a single amino acid substitution in MAP kinase 12 (MPK12). In parallel we showed that stomatal CO2-insensitivity phenotypes of a mutant cis (CO2-insensitive) were caused by a deletion of MPK12. Lack of MPK12 impaired bicarbonate-induced activation of S-type anion channels. We demonstrated that MPK12 interacted with the protein kinase HT1, a central node in guard cell CO2 signaling, and that MPK12 can function as an inhibitor of HT1. These data provide a new function for plant MPKs as protein kinase inhibitors and suggest a mechanism through which guard cell CO2 signaling controls plant water management.
%U https://www.biorxiv.org/content/biorxiv/early/2016/09/01/073015.full.pdf