Additional file 5: of Characterization of a strong and constitutive promoter from the Arabidopsis serine carboxypeptidase-like gene AtSCPL30 as a potential tool for crop transgenic breeding JiangPingping ZhangKe DingZhaohua HeQiuxia LiWendi ZhuShuangfeng ChengWen ZhangKewei LiKunpeng 2018 Figure S4. GUS staining of detached leaves of Nicotiana benthamiana transgenic plants under normal and salt-stress conditions. Ninety leaf discs (diameter 0.5 cm) from fifteen 60-day-old individual plants (5 individual plants/ line, 3 lines for each construct) of PD1-PD9 and CaMV35S transgenic plants were incubated in liquid 1/2 MS medium supplemented with 200 mM NaCl at 25 °C for 3, 6, 12, 24, 48, and 72 h; leaf discs floated in liquid 1/2 MS medium were used as control. The leaf discs of PD1-PD9 and CaMV35S transgenic plants were then incubated in staining solution at 37 °C for 3 h. Finally, the samples were observed and photographed after decolorization. (JPG 3572 kb)