%0 Journal Article %1 graus2018vppase %A Graus, D. %A Konrad, K. R. %A Bemm, F. %A Patir Nebioglu, M. G. %A Lorey, C. %A Duscha, K. %A Guthoff, T. %A Herrmann, J. %A Ferjani, A. %A Cuin, T. A. %A Roelfsema, M. R. G. %A Schumacher, K. %A Neuhaus, H. E. %A Marten, I. %A Hedrich, R. %D 2018 %J New Phytol %K Cell Death/drug effects myOwn uni_network %N 4 %P 1421-1432 %R 10.1111/nph.15280 %T High V-PPase activity is beneficial under high salt loads, but detrimental without salinity %U https://www.ncbi.nlm.nih.gov/pubmed/29938800 %V 219 %X The membrane-bound proton-pumping pyrophosphatase (V-PPase), together with the V-type H(+) -ATPase, generates the proton motive force that drives vacuolar membrane solute transport. Transgenic plants constitutively overexpressing V-PPases were shown to have improved salinity tolerance, but the relative impact of increasing PP(i) hydrolysis and proton-pumping functions has yet to be dissected. For a better understanding of the molecular processes underlying V-PPase-dependent salt tolerance, we transiently overexpressed the pyrophosphate-driven proton pump (NbVHP) in Nicotiana benthamiana leaves and studied its functional properties in relation to salt treatment by primarily using patch-clamp, impalement electrodes and pH imaging. NbVHP overexpression led to higher vacuolar proton currents and vacuolar acidification. After 3 d in salt-untreated conditions, V-PPase-overexpressing leaves showed a drop in photosynthetic capacity, plasma membrane depolarization and eventual leaf necrosis. Salt, however, rescued NbVHP-hyperactive cells from cell death. Furthermore, a salt-induced rise in V-PPase but not of V-ATPase pump currents was detected in nontransformed plants. The results indicate that under normal growth conditions, plants need to regulate the V-PPase pump activity to avoid hyperactivity and its negative feedback on cell viability. Nonetheless, V-PPase proton pump function becomes increasingly important under salt stress for generating the pH gradient necessary for vacuolar proton-coupled Na(+) sequestration.

@article{graus2018vppase, abstract = {The membrane-bound proton-pumping pyrophosphatase (V-PPase), together with the V-type H(+) -ATPase, generates the proton motive force that drives vacuolar membrane solute transport. Transgenic plants constitutively overexpressing V-PPases were shown to have improved salinity tolerance, but the relative impact of increasing PP(i) hydrolysis and proton-pumping functions has yet to be dissected. For a better understanding of the molecular processes underlying V-PPase-dependent salt tolerance, we transiently overexpressed the pyrophosphate-driven proton pump (NbVHP) in Nicotiana benthamiana leaves and studied its functional properties in relation to salt treatment by primarily using patch-clamp, impalement electrodes and pH imaging. NbVHP overexpression led to higher vacuolar proton currents and vacuolar acidification. After 3 d in salt-untreated conditions, V-PPase-overexpressing leaves showed a drop in photosynthetic capacity, plasma membrane depolarization and eventual leaf necrosis. Salt, however, rescued NbVHP-hyperactive cells from cell death. Furthermore, a salt-induced rise in V-PPase but not of V-ATPase pump currents was detected in nontransformed plants. The results indicate that under normal growth conditions, plants need to regulate the V-PPase pump activity to avoid hyperactivity and its negative feedback on cell viability. Nonetheless, V-PPase proton pump function becomes increasingly important under salt stress for generating the pH gradient necessary for vacuolar proton-coupled Na(+) sequestration.}, added-at = {2024-02-15T15:08:22.000+0100}, author = {Graus, D. and Konrad, K. R. and Bemm, F. and Patir Nebioglu, M. G. and Lorey, C. and Duscha, K. and Guthoff, T. and Herrmann, J. and Ferjani, A. and Cuin, T. A. and Roelfsema, M. R. G. and Schumacher, K. and Neuhaus, H. E. and Marten, I. and Hedrich, R.}, biburl = {https://www.bibsonomy.org/bibtex/2deb6c9fa784bd762e4c6e18abe22394c/jvsi_all}, doi = {10.1111/nph.15280}, interhash = {fb361aa2101ac1fd91b810123c3aefda}, intrahash = {deb6c9fa784bd762e4c6e18abe22394c}, issn = {1469-8137 (Electronic) 0028-646X (Print) 0028-646X (Linking)}, journal = {New Phytol}, keywords = {Cell Death/drug effects myOwn uni_network}, note = {Graus, Dorothea Konrad, Kai R Bemm, Felix Patir Nebioglu, Meliha Gorkem Lorey, Christian Duscha, Kerstin Guthoff, Tilman Herrmann, Johannes Ferjani, Ali Cuin, Tracey Ann Roelfsema, M Rob G Schumacher, Karin Neuhaus, H Ekkehard Marten, Irene Hedrich, Rainer eng Research Support, Non-U.S. Gov't England 2018/06/26 New Phytol. 2018 Sep;219(4):1421-1432. doi: 10.1111/nph.15280. Epub 2018 Jun 25.}, number = 4, pages = {1421-1432}, timestamp = {2024-02-15T15:11:55.000+0100}, title = {High V-PPase activity is beneficial under high salt loads, but detrimental without salinity}, type = {Journal Article}, url = {https://www.ncbi.nlm.nih.gov/pubmed/29938800}, volume = 219, year = 2018 }