@article{GajdanowiczMichardSandmannetal.2011,
  author    = {Gajdanowicz, Pawel and Michard, Erwan and Sandmann, Michael and Rocha, Marcio and Correa, Luiz Gustavo Guedes and Ramirez-Aguilar, Santiago J. and Gomez-Porras, Judith L. and Gonzalez, Wendy and Thibaud, Jean-Baptiste and van Dongen, Joost T. and Dreyer, Ingo},
  title     = {Potassium (K plus ) gradients serve as a mobile energy source in plant vascular tissues},
  series = {Proceedings of the National Academy of Sciences of the United States of America},
  volume    = {108},
  journal   = {Proceedings of the National Academy of Sciences of the United States of America},
  number    = {2},
  publisher = {National Acad. of Sciences},
  address   = {Washington},
  issn      = {0027-8424},
  doi       = {10.1073/pnas.1009777108},
  pages     = {864 -- 869},
  year      = {2011},
  abstract  = {The essential mineral nutrient potassium (K(+)) is the most important inorganic cation for plants and is recognized as a limiting factor for crop yield and quality. Nonetheless, it is only partially understood how K(+) contributes to plant productivity. K(+) is used as a major active solute to maintain turgor and to drive irreversible and reversible changes in cell volume. K(+) also plays an important role in numerous metabolic processes, for example, by serving as an essential cofactor of enzymes. Here, we provide evidence for an additional, previously unrecognized role of K(+) in plant growth. By combining diverse experimental approaches with computational cell simulation, we show that K(+) circulating in the phloem serves as a decentralized energy storage that can be used to overcome local energy limitations. Posttranslational modification of the phloem-expressed Arabidopsis K(+) channel AKT2 taps this "potassium battery," which then efficiently assists the plasma membrane H(+)-ATPase in energizing the transmembrane phloem (re) loading processes.},
  language  = {en}
}
@article{HeldPascaudEckertetal.2011,
  author    = {Held, Katrin and Pascaud, Francois and Eckert, Christian and Gajdanowicz, Pawel and Hashimoto, Kenji and Corratge-Faillie, Claire and Offenborn, Jan Niklas and Lacombe, Benoit and Dreyer, Ingo and Thibaud, Jean-Baptiste and Kudla, J{\"o}rg},
  title     = {Calcium-dependent modulation and plasma membrane targeting of the AKT2 potassium channel by the CBL4/CIPK6 calcium sensor/protein kinase complex},
  series = {Cell research},
  volume    = {21},
  journal   = {Cell research},
  number    = {7},
  publisher = {Nature Publ. Group},
  address   = {Shanghai},
  issn      = {1001-0602},
  doi       = {10.1038/cr.2011.50},
  pages     = {1116 -- 1130},
  year      = {2011},
  abstract  = {Potassium (K(+)) channel function is fundamental to many physiological processes. However, components and mechanisms regulating the activity of plant K(+) channels remain poorly understood. Here, we show that the calcium (Ca(2+)) sensor CBL4 together with the interacting protein kinase CIPK6 modulates the activity and plasma membrane (PM) targeting of the K(+) channel AKT2 from Arabidopsis thaliana by mediating translocation of AKT2 to the PM in plant cells and enhancing AKT2 activity in oocytes. Accordingly, akt2, cbl4 and cipk6 mutants share similar developmental and delayed flowering phenotypes. Moreover, the isolated regulatory C-terminal domain of CIPK6 is sufficient for mediating CBL4- and Ca(2+)-dependent channel translocation from the endoplasmic reticulum membrane to the PM by a novel targeting pathway that is dependent on dual lipid modifications of CBL4 by myristoylation and palmitoylation. Thus, we describe a critical mechanism of ion-channel regulation where a Ca(2+) sensor modulates K(+) channel activity by promoting a kinase interaction-dependent but phosphorylation-independent translocation of the channel to the PM.},
  language  = {en}
}