Calcium transport across plant membranes : mechanisms and functions
© 2018 The Authors. New Phytologist © 2018 New Phytologist Trust.
Veröffentlicht in: | The New phytologist. - 1979. - 220(2018), 1 vom: 18. Okt., Seite 49-69 |
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1. Verfasser: | |
Weitere Verfasser: | , , , |
Format: | Online-Aufsatz |
Sprache: | English |
Veröffentlicht: |
2018
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Zugriff auf das übergeordnete Werk: | The New phytologist |
Schlagworte: | Journal Article Research Support, Non-U.S. Gov't Review ROS-Ca2+ hub calcium calcium extrusion systems cyclic nucleotide-gated channels ion channels ionotropic glutamate receptors reactive oxygen species mehr... |
Zusammenfassung: | © 2018 The Authors. New Phytologist © 2018 New Phytologist Trust. Contents Summary 49 I. Introduction 49 II. Physiological and structural characteristics of plant Ca2+ -permeable ion channels 50 III. Ca2+ extrusion systems 61 IV. Concluding remarks 64 Acknowledgements 64 References 64 SUMMARY: Calcium is an essential structural, metabolic and signalling element. The physiological functions of Ca2+ are enabled by its orchestrated transport across cell membranes, mediated by Ca2+ -permeable ion channels, Ca2+ -ATPases and Ca2+ /H+ exchangers. Bioinformatics analysis has not determined any Ca2+ -selective filters in plant ion channels, but electrophysiological tests do reveal Ca2+ conductances in plant membranes. The biophysical characteristics of plant Ca2+ conductances have been studied in detail and were recently complemented by molecular genetic approaches. Plant Ca2+ conductances are mediated by several families of ion channels, including cyclic nucleotide-gated channels (CNGCs), ionotropic glutamate receptors, two-pore channel 1 (TPC1), annexins and several types of mechanosensitive channels. Key Ca2+ -mediated reactions (e.g. sensing of temperature, gravity, touch and hormones, and cell elongation and guard cell closure) have now been associated with the activities of specific subunits from these families. Structural studies have demonstrated a unique selectivity filter in TPC1, which is passable for hydrated divalent cations. The hypothesis of a ROS-Ca2+ hub is discussed, linking Ca2+ transport to ROS generation. CNGC inactivation by cytosolic Ca2+ , leading to the termination of Ca2+ signals, is now mechanistically explained. The structure-function relationships of Ca2+ -ATPases and Ca2+ /H+ exchangers, and their regulation and physiological roles are analysed |
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Beschreibung: | Date Completed 01.10.2019 Date Revised 30.09.2020 published: Print-Electronic Citation Status MEDLINE |
ISSN: | 1469-8137 |
DOI: | 10.1111/nph.15266 |