Fig. 6. ZmNSA1 regulates PM-H⁺-ATPase-mediated H⁺ efflux.

a, b Rhizosphere acidification assays of ZmNSA1^UFMu (a), ZmNSA1-overexpressing plants (b) and their wild type controls (W22 for ZmNSA1^UFMu, and Wild type for ZmNSA1-overexpressing plants). Yellow color indicated the acidification of the medium. c–f NMT assays of H⁺ flux at root meristem zone of five-days-old seedlings that have been treated with alkaline (pH 8.0) (c, e) or saline-alkaline stress (100 mM NaCl, pH 8.0) (d, f) for 24 hours. The H⁺ flux were measured using NMT (see Materials and methods). Data were means ± s.d. n = 5. g–j The activity of PM-H⁺-ATPase in plasma membrane vesicles isolated from the roots of NaHCO₃ treated plants (genotypes as indicated). The assays were performed as described in Materials and Methods. The data showed the timely varying curves of quinacrine fluorescent intensity (g, i) and the calculated activity of PM-H⁺-ATPase (h, j). Data were means ± s.d. of three independent experiments. Statistical significance was determined by a two-sided t-test. Source data underlying Fig. 6c–j are provided as a Source Data file.