Fig. 2.

Expression of constructs containing BvNHX1 full-size promoter, promoter sequence upstream of the 5′ UTR, and 5′ UTR including intron. a Constructs used. Upstream promoter sequence, 5′ UTR, and intron are marked in gray, black and white, respectively. Nucleotides are numbered in according to the translation start ATG start sequence. b Histochemical staining of seedlings germinated and grown on solid medium without or with salt. Homozygous seeds of Arabidopsis transformed with the indicated constructs were sown on plates containing 0.5× MS solid medium (0) or the same medium supplemented with 50 mM NaCl (50). Two-week-old seedlings were stained for GUS. c Quantitative GUS expression in non-stressed and stressed Arabidopsis seedlings. GUS activity was assayed in homogenates of homozygous seedlings described in (b). Data shown represent average activity determined in homogenates prepared from 50 seedlings each of five independent lines of each constructs germinated and grown for 2 weeks on plates containing solid 0.5× MS medium without (white bars) or containing in addition 50 mM NaCl (black bars), 25 mM Na₂SO₄ (diagonally dashed), 50 mM KCl (dotted), 100 mM mannitol (horizontally dashed), or 20 μM ABA (vertically dashed). Activity is normalized to allow averaging between different transgenic lines and different experiments. GUS activities of L1::GUS and S1::GUS constructs under control conditions were similar, and were not statistically different