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| Entry URI | http://metadb.riken.jp/db/SciNetS_ria224i/cria224u4ria224u14535887i |
| Entry name | Apse Maris P et al. 2003 Oct. Plant J. 36(2):229-39. |
| Title | Vacuolar cation/H+ exchange, ion homeostasis, and leaf development are altered in a T-DNA insertional mutant of AtNHX1, the Arabidopsis vacuolar Na+/H+ antiporter. |
| Authors | Apse Maris P|Blumwald Eduardo|Sottosanto Jordan B |
| Abstract | The function of vacuolar Na+/H+ antiporter(s) in plants has been studied primarily in the context of salinity tolerance. By facilitating the accumulation of Na+ away from the cytosol, plant cells can avert ion toxicity and also utilize vacuolar Na+ as osmoticum to maintain turgor. As many genes encoding these antiporters have been cloned from salt-sensitive plants, it is likely that they function in some capacity other than salinity tolerance. The wide expression pattern of Arabidopsis thaliana sodium proton exchanger 1 (AtNHX1) in this study supports this hypothesis. Here, we report the isolation of a T-DNA insertional mutant of AtNHX1, a vacuolar Na+/H+ antiporter in Arabidopsis. Vacuoles isolated from leaves of the nhx1 plants had a much lower Na+/H+ and K+/H+ exchange activity. nhx1 plants also showed an altered leaf development, with reduction in the frequency of large epidermal cells and a reduction in overall leaf area compared to wild-type plants. The overexpression of AtNHX1 in the nhx1 background complemented these phenotypes. In the presence of NaCl, nhx1 seedling establishment was impaired. These results place AtNHX1 as the dominant K+ and Na+/H+ antiporter in leaf vacuoles in Arabidopsis and also suggest that its contribution to ion homeostasis is important for not only salinity tolerance but development as well. |
| Pubmed ID | 14535887 |
| Journal | The Plant journal |
| Volume | 36 |
| Issue | 2 |
| Pages | 229-39 |
| Publication date | 2003 Oct |
| Num of phenotype gene | 2 |