Vacuolar two-pore K+ channels act as vacuolar osmosensors
© 2011 The Author. New Phytologist © 2011 New Phytologist Trust.
| Veröffentlicht in: | The New phytologist. - 1979. - 191(2011), 1 vom: 06. Juli, Seite 84-91 |
|---|---|
| 1. Verfasser: | |
| Format: | Online-Aufsatz |
| Sprache: | English |
| Veröffentlicht: |
2011
|
| Zugriff auf das übergeordnete Werk: | The New phytologist |
| Schlagworte: | Journal Article Research Support, Non-U.S. Gov't Plant Proteins Potassium Channels |
| Zusammenfassung: | © 2011 The Author. New Phytologist © 2011 New Phytologist Trust. • Plant two-pore K(+) channels (TPKs) have been shown previously to play a role in vacuolar K(+) homeostasis. TPK activity is insensitive to membrane voltage, but regulated by cytoplasmic calcium and 14-3-3 proteins. This study reports that membrane stretch and osmotic gradients also alter the activity of TPKs from Arabidopsis, rice and barley, and that this may have a physiological relevance for osmotic homeostasis. • Mechanosensitivity was studied using patch clamp experiments and TPKs from Arabidopsis, rice and barley. In addition, the capability of TPKs to act as osmosensors was determined. By using protoplast disruption assays and intact plant survival assays, in genotypes that differed in TPK expression, the physiological relevance of TPK-based osmosensing was tested. • TPKs from all three species showed varying degrees of mechanosensitivity. TPK activity in channels from all three species was sensitive to trans-tonoplast osmotic gradients. TPK osmosensing is likely to proceed via the detection of small perturbations in membrane tension. Intact plant and protoplast assays showed that TPK-based osmosensing is important during exposure to rapid changes in external osmolarity. • Vacuolar TPK channels can act as intracellular osmosensors and rapidly increase channel activity during hypo-osmotic shock to release vacuolar K(+) |
|---|---|
| Beschreibung: | Date Completed 03.10.2011 Date Revised 29.05.2025 published: Print-Electronic Citation Status MEDLINE |
| ISSN: | 1469-8137 |
| DOI: | 10.1111/j.1469-8137.2011.03664.x |