Root plasma membrane H+-ATPase is involved in the adaptation of soybean to phosphorus starvation

Abstract

The plasma membrane H+-ATPase plays an important role in the plant response to nutrient and environmental stresses. However, the involvement of plant root plasma membrane H+-ATPase in adaptation to phosphate (P) starvation is not yet fully elucidated. In this study, experiments were performed with soybean roots in low-P nutrient solution (10 microM). Treatment with fusicoccin, an activator of the plasma membrane H+-ATPase, increased P uptake by 35%, while vanadate, an inhibitor of plasma membrane H+-ATPase, severely suppressed it. These results suggested that P uptake might be regulated via the modulation of the activity of plasma membrane H+-ATPase under P starvation. The relationship between P uptake and the activity of plasma membrane H+-ATPase was examined further by using plasma membrane H+-ATPase transgenic Arabidopsis thaliana under low-P conditions. Transgenic plants absorbed more P compared with wild-type Arabidopsis. Results from real-time RT-PCR, western-blotting and immunolocalization analysis indicated that the increase in activity of the plasma membrane H+-ATPase by P starvation was caused by its transcriptional and translational regulation. A higher expression was observed at the translational level than at the transcriptional level. P starvation could induce a transient increase of endogenous indole-3-acetic acid (IAA) in soybean roots. The exogenous application of IAA stimulated the activity of plasma membrane H+-ATPase and P uptake, while naphthylphthalamic acid (NPA), an IAA transport inhibitor, blocked IAA effects. Taken together, these results suggested an involvement of root plasma membrane H+-ATPase in the adaptation of soybean to P starvation. IAA might be involved in signal transduction of P starvation by activating the plasma membrane H+-ATPase in soybean roots.

The plasma membrane H+-ATPase is related to the development of salicylic acid-induced thermotolerance in pea leaves

“…It is also modulated by calcium ions, abscisic acid, auxin, cGMP, light, phospholipids and kinases (Kinoshita et al 1995;Michelet and Boutry 1995;Suwastika and Gehring 1999;Peng et al 2003). Furthermore, the activity and gene expression of this enzyme are affected by various environmental factors, such as phosphorus starvation (Shen et al 2006), Al stress (Ahn et al 2001) and salinity (Vitart et al 2001;Yang et al 2007). An induced PM H ?…”

Response of Phosphate Solubilising Inoculants (Jumpstart) on Biochemistry and Yield of Rice (Oryza sativa L.)

“…At 50% flowering stage the ATPase activity at 0% P was 57.48 and 48.9% higher in comparison with 100% P levels ( Table 4). Hong Shen et al, (2006) found that P starvation enhanced the activity of plasma membrane H + -ATPase in soybean roots. The plasma membrane derived from active proteoid roots of P-deficient plants showed a more than two times higher ATPase activity than P-sufficient roots.…”

Resistance to Herbicides in the Model Organisms Saccharomyces cerevisiae and Arabidopsis thaliana: the Involvement of Multidrug Resistance Transporters

“…In acidified growth medium, suitable for fungal growth, yeast cells challenged with the herbicide 2,4-D suffer a strong reduction in their cytosolic and vacuolar pH Simões et al, 2003), which is counteracted by the activation of the plasma and vacuolar membrane H + -ATPases Teixeira et al, 2005). Significantly, auxins were also shown to induce the activity of the Arabidopsis plasma membrane H + -ATPase, contributing to maintain the intracellular pH in plant roots (Shen et al, 2006). Based on the participation of the MDR transporters Tpo1p and Pdr5p (belonging to the MFS and ABC superfamily, respectively) in yeast resistance to 2,4-D, the active export of the 2,4-D counter-ion catalysed by these plasma membrane transporters was postulated (Teixeira & Sá-Correia, 2002).…”