title: Identification and characterization of a PutAMT1;1 gene from Puccinellia tenuiflora.
abstract: Nitrogen is one of the most important limiting factors for plant growth. However, as ammonium is readily converted into ammonia (NH3) when soil pH rises above 8.0, this activity depletes the availability of ammonium (NH4(+)) in alkaline soils, consequently preventing the growth of most plant species. The perennial wild grass Puccinellia tenuiflora is one of a few plants able to grow in soils with extremely high salt and alkaline pH (>9.0) levels. Here, we assessed how this species responds to ammonium under such conditions by isolating and analyzing the functions of a putative ammonium transporter (PutAMT1;1). PutAMT1;1 is the first member of the AMT1 (ammonium transporter) family that has been identified in P. tenuiflora. This gene (1) functionally complemented a yeast mutant deficient in ammonium uptake (2), is preferentially expressed in the anther of P. tenuiflora, and (3) is significantly upregulated by ammonium ions in both the shoot and roots. The PutAMT1;1 protein is localized in the plasma membrane and around the nuclear periphery in yeast cells and P. tenuiflora suspension cells. Immunoelectron microscopy analysis also indicated that PutAMT1;1 is localized in the endomembrane. The overexpression of PutAMT1;1 in A. thaliana enhanced plant growth, and increased plant susceptibility to toxic methylammonium (MeA). Here, we confirmed that PutAMT1;1 is an ammonium-inducible ammonium transporter in P. tenuiflora. On the basis of the results of PutAMT1;1 overexpression in A. thaliana, this gene might be useful for improving the root to shoot mobilization of MeA (or NH4(+)).
authors: Key Laboratory of Saline-Alkali Vegetation Ecology Restoration in Oil Field (SAVER), Ministry of Education, Alkali Soil Natural Environmental Science Center, Northeast Forestry University, Harbin, P.R.China.
authors: Yuanyuan
authors: Y
authors: Bu
authors: Bo
authors: B
authors: Sun
authors: Aimin
authors: A
authors: Zhou
authors: Xinxin
authors: X
authors: Zhang
authors: Imshik
authors: I
authors: Lee
authors: Shenkui
authors: S
authors: Liu
mesh_terms: D064751:Ammonium Compounds / Q000378:metabolism*; D017360:Arabidopsis / Q000235:genetics; D001483:Base Sequence; D027682:Cation Transport Proteins / Q000378:metabolism*; D003001:Cloning, Molecular; D020869:Gene Expression Profiling; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant; D006863:Hydrogen-Ion Concentration; D007477:Ions; D008969:Molecular Sequence Data; D009584:Nitrogen / Q000378:metabolism; D016366:Open Reading Frames; D010802:Phylogeny; D010940:Plant Proteins / Q000378:metabolism*; D018517:Plant Roots / Q000235:genetics / Q000378:metabolism; D018520:Plant Shoots / Q000378:metabolism; D030821:Plants, Genetically Modified / Q000235:genetics / Q000378:metabolism; D010957:Plasmids; D006109:Poaceae / Q000235:genetics* / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000378:metabolism; D055051:Salt-Tolerant Plants / Q000235:genetics / Q000378:metabolism; D012965:Sodium Chloride / Q000378:metabolism
chemical_list: D064751:Ammonium Compounds; D027682:Cation Transport Proteins; D007477:Ions; D010940:Plant Proteins; C088952:ammonium transporters, plant; D012965:Sodium Chloride; D009584:Nitrogen