Abstract
Examination of aquaporin (AQP) membrane channels in extremophile plants may increase our understanding of plant tolerance to high salt, drought or other conditions. Here, we cloned a tonoplast AQP gene (TsTIP1;2) from the halophyte Thellungiella salsuginea and characterized its biological functions. TsTIP1;2 transcripts accumulate to high levels in several organs, increasing in response to multiple external stimuli. Ectopic overexpression of TsTIP1;2 in Arabidopsis significantly increased plant tolerance to drought, salt and oxidative stresses. TsTIP1;2 had water channel activity when expressed in Xenopus oocytes. TsTIP1;2 was also able to conduct H2O2 molecules into yeast cells in response to oxidative stress. TsTIP1;2 was not permeable to Na+ in Xenopus oocytes, but it could facilitate the entry of Na+ ions into plant cell vacuoles by an indirect process under high-salinity conditions. Collectively, these data showed that TsTIP1;2 could mediate the conduction of both H2O and H2O2 across membranes, and may act as a multifunctional contributor to survival of T. salsuginea in highly stressful habitats.
Original language | English (US) |
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Pages (from-to) | 148-161 |
Number of pages | 14 |
Journal | Plant and Cell Physiology |
Volume | 55 |
Issue number | 1 |
DOIs | |
State | Published - Jan 2014 |
Keywords
- Aquaporin
- Channeling activity
- Stress tolerance
- Thellungiella salsuginea
ASJC Scopus subject areas
- Physiology
- Plant Science
- Cell Biology