Coordinate up-regulation of V-H+-ATPase and vacuolar Na+/H+ antiporter as a response to NaCl treatment in a C3 halophyte Suaeda salsa

Global plant-responding mechanisms to salt stress: physiological and molecular levels and implications in biotechnology

“…In genetic engineering, the hypersensitive phenotype of sos1 demonstrated the key position of the SOS signaling pathway during salt-stress. Compared to control leaves, the H + -ATPase in tonoplast vesicles increased 2-fold in salt-treated leaves (Qiu et al, 2007). Overexpression of NHX may reduce the cytosolic Na + concentration and improve salt tolerance by efficient sequestration (Apse et al, 1999).…”

Regulation by salt of vacuolar H+-ATPase and H+-pyrophosphatase activities and Na+/H+exchange

“…24 A general sodium-induced increase in V-H + -ATPase activity in plant response to salt has been reported. 35,37,38,41,42,44,45,47,[49][50][51][52][53][54][55][56] In contrast, the activity of V-H + -ATPase in Daucus carrota was unaffected by salt treatment 43 and was even repressed in wheat roots under severe NaCl stress. 40 In the halophyte S. salsa, the main strategy of salt-tolerance seems to be an upregulation of V-H + -ATPase.…”

“…47 The hydrolytic and H + pumping activity of the V-H + -ATPase in tonoplast vesicles derived from leaves increased two-fold in salt-treated leaves (200 mM NaCl) compared with the control leaves. 56 In Mesembryanthemum crystallinum, where the tonoplast ATPase seems to be the main enzyme responsible for the energization of malate accumulation in Crassulacean acid metabolism (CAM), 38 both V-H + -ATPase H + -transport and ATP hydrolytic activity were twofold higher in vesicles isolated from leaves of plants treated with 200 mM NaCl when compared with the activity measured in control plants. 51 In Populus euphratica, studies showed that cell suspensions respond to salt stress by increasing both the V-H + -ATPase hydrolytic 42,55 and H + pumping activities.…”

“…3). Some reports show upregulation of NHX genes, 22,56,[72][73][74][75][76][77]79,80,99 increased protein abundance 56,[74][75][76] or regulation at protein activity level. 46,100 Garbarino and co-workers 97,100 have shown that the inducible Na + /H + antiporter activity observed in tonoplast from barley roots grown in the presence of NaCl was due to activation of an existing protein rather than to de novo protein synthesis, since the rapid induction was observed in the presence of inhibitors of protein synthesis.…”

“…As shown below, there can be coordination of activity between the exchangers on the tonoplast and plasma membranes 101 and the C-terminus of AtNHX1, which may face the vacuolar lumen, 84 may have a key role in the regulation of the protein activity by binding calmodulin. 102 Moreover, in A. gmelini, 74 B. vulgaris, 75 B. napus 76 and S. salsa, 56 upregulation of the tonoplast Na + /H + antiport activity is due to increase of both transcription and translation. A crosstalk between osmotic stress and vacuole accumulation of Na + has been demonstrated in Arabidopsis where osmotic stress activates the synthesis of abscisic acid (ABA), which upregulates the transcription of AtNHX1.…”