Analysis of Reactive Oxygen Species (ROS) production
Total ROS were measured in control and AsIII-treated WT andCsGGCT2;1 overexpressing (OE) seedlings by using the fluorescent
dye 2′,7′-dichlorofluorescein diacetate (DCFDA). Roots were soaked in a
solution of 1 mM DCFDA for 15 min in the dark, washed, and imaged. A
Nikon Eclipse Ni microscope equipped with a DS-Ri2 digital camera (Nikon
Instruments Inc., Melville, NY) was used for imaging. The fluorescence
from H2DCFDA was observed under eGFP epifluorescence
(Ex470-440, DM4951p, BA525/550) with exposure time set at 150
milliseconds at 4x magnification. ImageJ software was used to quantify
the average signal intensity in regions of interest (1cm of root tip).