The Thellungiella salsuginea tonoplast aquaporin TsTIP1;2 functions in protection against multiple abiotic stresses.
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.
Institute of Microbiology, University of Chinese Academy of Sciences, Beijing, 100101 China.
Li-Li
LL
Wang
An-Ping
AP
Chen
Nai-Qin
NQ
Zhong
Ning
N
Liu
Xiao-Min
XM
Wu
Fang
F
Wang
Chun-Lin
CL
Yang
Michael F
MF
Romero
Gui-Xian
GX
Xia
D000818:Animals; D020346:Aquaporins / Q000378:metabolism*; D017360:Arabidopsis / Q000235:genetics / Q000502:physiology; D001692:Biological Transport / Q000187:drug effects; D019607:Brassicaceae / Q000187:drug effects / Q000235:genetics / Q000502:physiology*; D003001:Cloning, Molecular; D004058:Diffusion; D055864:Droughts; D020869:Gene Expression Profiling; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D017343:Genes, Plant / Q000235:genetics; D049452:Green Fluorescent Proteins / Q000378:metabolism; D006861:Hydrogen Peroxide / Q000378:metabolism; D007425:Intracellular Membranes / Q000187:drug effects / Q000378:metabolism; D009865:Oocytes / Q000187:drug effects / Q000378:metabolism; D018384:Oxidative Stress / Q000187:drug effects / Q000235:genetics; D010802:Phylogeny; D030821:Plants, Genetically Modified; D021381:Protein Transport / Q000187:drug effects; D012964:Sodium / Q000378:metabolism; D012965:Sodium Chloride / Q000494:pharmacology; D013312:Stress, Physiological / Q000187:drug effects / Q000235:genetics; D013347:Subcellular Fractions / Q000187:drug effects / Q000378:metabolism; D014617:Vacuoles / Q000187:drug effects / Q000378:metabolism*; D014867:Water / Q000378:metabolism; D014981:Xenopus
D020346:Aquaporins; D014867:Water; D049452:Green Fluorescent Proteins; D012965:Sodium Chloride; D012964:Sodium; D006861:Hydrogen Peroxide
Aquaporin; Channeling activity; Stress tolerance; Thellungiella salsuginea