%0 Journal Article %1 gutermuth2018tiplocalized %A Gutermuth, T. %A Herbell, S. %A Lassig, R. %A Brosche, M. %A Romeis, T. %A Feijo, J. A. %A Hedrich, R. %A Konrad, K. R. %D 2018 %J New Phytol %K Animals myOwn %N 3 %P 1089-1105 %R 10.1111/nph.15067 %T Tip-localized Ca(2+) -permeable channels control pollen tube growth via kinase-dependent R- and S-type anion channel regulation %U https://www.ncbi.nlm.nih.gov/pubmed/29522235 %V 218 %X Pollen tubes (PTs) are characterized by having tip-focused cytosolic calcium ion (Ca(2+) ) concentration (Ca(2+) (cyt) ) gradients, which are believed to control PT growth. However, the mechanisms by which the apical Ca(2+) (cyt) orchestrates PT growth are not well understood. Here, we aimed to identify these mechanisms by combining reverse genetics, cell biology, electrophysiology, and live-cell Ca(2+) and anion imaging. We triggered Ca(2+) -channel activation by applying hyperpolarizing voltage pulses and observed that the evoked Ca(2+) (cyt) increases were paralleled by high anion channel activity and a decrease in the cytosolic anion concentration at the PT tip. We confirmed a functional correlation between these patterns by showing that inhibition of Ca(2+) -permeable channels eliminated the Ca(2+) (cyt) increase, resulting in the abrogation of anion channel activity via Ca(2+) -dependent protein kinases (CPKs). Functional characterization of CPK and anion-channel mutants revealed a CPK2/20/6-dependent activation of SLAH3 and ALMT12/13/14 anion channels. The impaired growth phenotypes of anion channel and CPK mutants support the physiological significance of a kinase- and Ca(2+) -dependent pathway to control PT growth via anion channel activation. Other than unveiling this functional link, our membrane hyperpolarization method allows for unprecedented manipulation of the Ca(2+) (cyt) gradient or oscillations in the PT tips and opens an array of opportunities for channel screenings.

@article{gutermuth2018tiplocalized, abstract = {Pollen tubes (PTs) are characterized by having tip-focused cytosolic calcium ion (Ca(2+) ) concentration ([Ca(2+) ](cyt) ) gradients, which are believed to control PT growth. However, the mechanisms by which the apical [Ca(2+) ](cyt) orchestrates PT growth are not well understood. Here, we aimed to identify these mechanisms by combining reverse genetics, cell biology, electrophysiology, and live-cell Ca(2+) and anion imaging. We triggered Ca(2+) -channel activation by applying hyperpolarizing voltage pulses and observed that the evoked [Ca(2+) ](cyt) increases were paralleled by high anion channel activity and a decrease in the cytosolic anion concentration at the PT tip. We confirmed a functional correlation between these patterns by showing that inhibition of Ca(2+) -permeable channels eliminated the [Ca(2+) ](cyt) increase, resulting in the abrogation of anion channel activity via Ca(2+) -dependent protein kinases (CPKs). Functional characterization of CPK and anion-channel mutants revealed a CPK2/20/6-dependent activation of SLAH3 and ALMT12/13/14 anion channels. The impaired growth phenotypes of anion channel and CPK mutants support the physiological significance of a kinase- and Ca(2+) -dependent pathway to control PT growth via anion channel activation. Other than unveiling this functional link, our membrane hyperpolarization method allows for unprecedented manipulation of the [Ca(2+) ](cyt) gradient or oscillations in the PT tips and opens an array of opportunities for channel screenings.}, added-at = {2024-02-15T15:08:22.000+0100}, author = {Gutermuth, T. and Herbell, S. and Lassig, R. and Brosche, M. and Romeis, T. and Feijo, J. A. and Hedrich, R. and Konrad, K. R.}, biburl = {https://www.bibsonomy.org/bibtex/2fbcfc116452c5002e26218cac27be06b/jvsi_all}, doi = {10.1111/nph.15067}, interhash = {4b8fdc8adfba4484f395fde4f66181d4}, intrahash = {fbcfc116452c5002e26218cac27be06b}, issn = {1469-8137 (Electronic) 0028-646X (Linking)}, journal = {New Phytol}, keywords = {Animals myOwn}, note = {Gutermuth, Timo Herbell, Sarah Lassig, Roman Brosche, Mikael Romeis, Tina Feijo, Jose Alberto Hedrich, Rainer Konrad, Kai Robert eng Research Support, Non-U.S. Gov't England 2018/03/10 New Phytol. 2018 May;218(3):1089-1105. doi: 10.1111/nph.15067. Epub 2018 Mar 9.}, number = 3, pages = {1089-1105}, timestamp = {2024-02-15T15:08:22.000+0100}, title = {Tip-localized Ca(2+) -permeable channels control pollen tube growth via kinase-dependent R- and S-type anion channel regulation}, type = {Journal Article}, url = {https://www.ncbi.nlm.nih.gov/pubmed/29522235}, volume = 218, year = 2018 }