Characterization and expression of a vacuolar Na+/H+ antiporter gene from the monocot halophyte Aeluropus littoralis

Role of Na+/H+Antiporters in Na+Homeostasis in Halophytic Plants

“…Similar results of higher expression in root explants were observed in ThNHX1 (T. halophila) and AlNHX (A. littoralis) [102]. In other halophytes, NHX1 gene expression was found in leaf or foliar tissue.…”

Salt tolerance of halophytes, research questions reviewed in the perspective of saline agriculture

“…In so far salt tolerance would be comparable with heavy metal tolerance indeed, high-salt tolerance might be achieved mainly through copy number expansion and/or a deregulated, constitutive over-expression or repression of particular genes, usually a subset of those that are also involved in cation homeostasis or osmotic adaptation in glycophytes, rather than through changes of protein structure (Hanikenne and Nouet, 2011). There are several reports in line with this view (Taji et al, 2004;Inan et al, 2004;Kant et al, 2006;Zhang et al, 2008;Edelist et al, 2009;Sahu and Shaw, 2009). Many studies have checked the inducibility by salt exposure of supposed candidate tolerance genes in halophytes, or made larger-scale gene expression comparisons between salt-treated and untreated halophytes (Table 4), and concluded, in case of significant induction, that the genes in question are likely to be involved in the salt tolerance mechanism of the halophyte under study (Table 4).…”

Role of sodium and hydrogen (Na+/H+) antiporters in salt tolerance of plants: Present and future challenges

“…The TaNHX1 from the monocot wheat did not increase salt tolerance of the dicot Arabidopsis. On the contrary, Zhang et al (2008) isolated a vacuolar Na + /H + antiporter from the monocot halophyte species, Aeluropus littoralis. Expression of this AlNHX gene in tobacco, a dicot plant conferred very high salt tolerance.…”

“…In some other experiments, transgenic tobacco with HbNHX1, SynnhaP1 and AtNHX1 conferred salt stress tolerance (Lu et al, 2005;Hossain et al, 2006;Soliman et al, 2009). More importantly, transgenic tobacco with vacuolar Na + /H + antiporter (AlNHX1) from Aeluropus littoralis showed about 150% increase in plant dry weight under salt stress (Zhang et al, 2008). The expression of AgNHX1 in transgenic rice plants exhibited enhanced survival of seedlings (81 to 100%) under salt stress (Ohta et al, 2002).…”