4.10. Microscopic Imaging of GUS Staining and Fluorescence of DII-VENUS

GUS staining was carried out according to the method reported in Hu et al. [50]. GUS activity in primary root apices in 5-day-old DR5::GUS seedlings treated with 0, 25, 50, 100 μM Cd for 3–4 days on 1/2 MS plates. GUS-stained images were observed under a stereo microscope (ZEISS Stemi 2000-C) and photographed by a CCD camera (Canon PowerShot A620).

Confocal microscopy was performed using a confocal laser scanning microscope (PerkinElmer, Waltham, MA, USA, UltraVIEW^® VoX) according to the manufacturer’s instructions, excitation and emission wavelengths were 488 to 520 nm for DII-VENUS. Auxin signaling level in primary root apices in five-day-old Arabidopsis thaliana DII-VENUS seedlings treated with 0, 25, 50, 100 μM Cd for 3–4 days on 1/2 MS plates.