Phosphatase ABI1 and okadaic acid-sensitive phosphoprotein phosphatases inhibit salt stress-activated SnRK2.4 kinase

BMC Plant Biology

Research Article

Agnieszka Ludwików¹  Maria Bucholc²  Anna Kulik²  Małgorzata Lichocka²  Grażyna Dobrowolska²  Janusz Dębski²  Michał Dadlez³  Arkadiusz Ciesielski⁴  Ewa Krzywińska⁵  Pedro L. Rodriguez⁶ 

[1] Department of Biotechnology, Institute of Molecular Biology and Biotechnology, Faculty of Biology, Adam Mickiewicz University in Poznań, Umultowska 89, 61-614, Poznań, Poland;Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawińskiego 5a, 02-106, Warsaw, Poland;Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawińskiego 5a, 02-106, Warsaw, Poland;Institute of Genetics and Biotechnology, University of Warsaw, Pawińskiego 5a, 02-106, Warsaw, Poland;Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawińskiego 5a, 02-106, Warsaw, Poland;Present address: Department of Chemistry, Warsaw University, Pasteur 1, 02-093, Warsaw, Poland;Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawińskiego 5a, 02-106, Warsaw, Poland;Present address: Nencki Institute of Experimental Biology, Polish Academy of Sciences, Pasteur 3, 02-093, Warsaw, Poland;Instituto de Biología Molecular y Celular de Plantas, Consejo Superior de Investigaciones Científicas-Universidad Politécnica de Valencia, ES-46022, Valencia, Spain;

关键词: Salinity;    Osmotic stress signaling;    SNF1-related protein kinases 2;    SnRK2;    Phosphoprotein phosphatases;    Arabidopsis thaliana;    ABI1;    PPP;    PP2C;   

DOI  :  10.1186/s12870-016-0817-1

 received in 2015-12-11, accepted in 2016-05-23,  发布年份 2016

来源: Springer

【 摘 要 】

BackgroundSNF1-related protein kinases 2 (SnRK2s) are key regulators of the plant response to osmotic stress. They are transiently activated in response to drought and salinity. Based on a phylogenetic analysis SnRK2s are divided into three groups. The classification correlates with their response to abscisic acid (ABA); group 1 consists SnRK2s non-activated in response to ABA, group 2, kinases non-activated or weakly activated (depending on the plant species) by ABA treatment, and group 3, ABA-activated kinases. The activity of all SnRK2s is regulated by phosphorylation. It is well established that clade A phosphoprotein phosphatases 2C (PP2Cs) are negative regulators of ABA-activated SnRK2s, whereas regulators of SnRK2s from group 1 remain unidentified.ResultsHere, we show that ABI1, a PP2C clade A phosphatase, interacts with SnRK2.4, member of group 1 of the SnRK2 family, dephosphorylates Ser158, whose phosphorylation is needed for the kinase activity, and inhibits the kinase, both in vitro and in vivo. Our data indicate that ABI1 and the kinase regulate primary root growth in response to salinity; the phenotype of ABI1 knockout mutant (abi1td) exposed to salt stress is opposite to that of the snrk2.4 mutant. Moreover, we show that the activity of SnRK2s from group 1 is additionally regulated by okadaic acid-sensitive phosphatase(s) from the phosphoprotein phosphatase (PPP) family.ConclusionsPhosphatase ABI1 and okadaic acid-sensitive phosphatases of the PPP family are negative regulators of salt stress-activated SnRK2.4. The results show that ABI1 inhibits not only the ABA-activated SnRK2s but also at least one ABA-non-activated SnRK2, suggesting that the phosphatase is involved in the cross talk between ABA-dependent and ABA-independent stress signaling pathways in plants.

【 授权许可】

CC BY   
© The Author(s). 2016