%0 Journal Article %1 RN1084 %A Latz, A. %A Mehlmer, N. %A Zapf, S. %A Mueller, T. D. %A Wurzinger, B. %A Pfister, B. %A Csaszar, E. %A Hedrich, R. %A Teige, M. %A Becker, D. %D 2013 %J Molecular Plant %K channel myOwn potassium %N 4 %P 1274-1289 %R 10.1093/mp/sss158 %T Salt Stress Triggers Phosphorylation of the Vacuolar K Channel TPK1 by Calcium-Dependent Protein Kinases (CDPKs) %U /brokenurl#<Go to ISI>://WOS:000322410700020 %V 6 %X The Arabidopsis vacuolar two-pore K channel 1 (TPK1) interacts with the 1433 protein GRF6 (GF14-). Here, we report that this interaction requires activation of the 1433 binding motif in TPK1 by the calcium-dependent protein kinase CPK3. Cpk3 and tpk1 mutants displayed salt-sensitive phenotypes, providing evidence for an essential role of the vacuolar potassium channel TPK1 in Ca-2-dependent salt-stress adaptation.1433 proteins play an important role in the regulation of many cellular processes. The Arabidopsis vacuolar two-pore K channel 1 (TPK1) interacts with the 1433 protein GRF6 (GF14-). Upon phosphorylation of the putative binding motif in the N-terminus of TPK1, GRF6 binds to TPK1 and activates the potassium channel. In order to gain a deeper understanding of this 1433-mediated signal transduction, we set out to identify the respective kinases, which regulate the phosphorylation status of the 1433 binding motif in TPK1. Here, we report that the calcium-dependent protein kinases (CDPKs) can phosphorylate and thereby activate the 1433 binding motif in TPK1. Focusing on the stress-activated kinase CPK3, we visualized direct and specific interaction of TPK1 with the kinase at the tonoplast in vivo. In line with its proposed role in K homeostasis, TPK1 phosphorylation was found to be induced by salt stress in planta, and both cpk3 and tpk1 mutants displayed salt-sensitive phenotypes. Molecular modeling of the TPK1CPK3 interaction domain provided mechanistic insights into TPK1 stress-regulated phosphorylation responses and pinpointed two arginine residues in the N-terminal 1433 binding motif in TPK1 critical for kinase interaction. Taken together, our studies provide evidence for an essential role of the vacuolar potassium channel TPK1 in salt-stress adaptation as a target of calcium-regulated stress signaling pathways involving Ca-2, Ca-2-dependent kinases, and 1433 proteins.

@article{RN1084, abstract = {The Arabidopsis vacuolar two-pore K channel 1 (TPK1) interacts with the 1433 protein GRF6 (GF14-). Here, we report that this interaction requires activation of the 1433 binding motif in TPK1 by the calcium-dependent protein kinase CPK3. Cpk3 and tpk1 mutants displayed salt-sensitive phenotypes, providing evidence for an essential role of the vacuolar potassium channel TPK1 in Ca-2-dependent salt-stress adaptation.1433 proteins play an important role in the regulation of many cellular processes. The Arabidopsis vacuolar two-pore K channel 1 (TPK1) interacts with the 1433 protein GRF6 (GF14-). Upon phosphorylation of the putative binding motif in the N-terminus of TPK1, GRF6 binds to TPK1 and activates the potassium channel. In order to gain a deeper understanding of this 1433-mediated signal transduction, we set out to identify the respective kinases, which regulate the phosphorylation status of the 1433 binding motif in TPK1. Here, we report that the calcium-dependent protein kinases (CDPKs) can phosphorylate and thereby activate the 1433 binding motif in TPK1. Focusing on the stress-activated kinase CPK3, we visualized direct and specific interaction of TPK1 with the kinase at the tonoplast in vivo. In line with its proposed role in K homeostasis, TPK1 phosphorylation was found to be induced by salt stress in planta, and both cpk3 and tpk1 mutants displayed salt-sensitive phenotypes. Molecular modeling of the TPK1CPK3 interaction domain provided mechanistic insights into TPK1 stress-regulated phosphorylation responses and pinpointed two arginine residues in the N-terminal 1433 binding motif in TPK1 critical for kinase interaction. Taken together, our studies provide evidence for an essential role of the vacuolar potassium channel TPK1 in salt-stress adaptation as a target of calcium-regulated stress signaling pathways involving Ca-2, Ca-2-dependent kinases, and 1433 proteins.}, added-at = {2024-02-14T14:38:32.000+0100}, author = {Latz, A. and Mehlmer, N. and Zapf, S. and Mueller, T. D. and Wurzinger, B. and Pfister, B. and Csaszar, E. and Hedrich, R. and Teige, M. and Becker, D.}, biburl = {https://www.bibsonomy.org/bibtex/2f9c3d253e9b974c00b052e99735aec3e/rainerhedrich_2}, doi = {10.1093/mp/sss158}, interhash = {774876b137f719fffe491056a03c7b94}, intrahash = {f9c3d253e9b974c00b052e99735aec3e}, issn = {1674-2052}, journal = {Molecular Plant}, keywords = {channel myOwn potassium}, note = {191kb Times Cited:139 Cited References Count:82}, number = 4, pages = {1274-1289}, timestamp = {2024-02-14T14:38:32.000+0100}, title = {Salt Stress Triggers Phosphorylation of the Vacuolar K Channel TPK1 by Calcium-Dependent Protein Kinases (CDPKs)}, type = {Journal Article}, url = {/brokenurl#<Go to ISI>://WOS:000322410700020}, volume = 6, year = 2013 }