Comparison of EdU-based and BrdU-based replication assays on Arabidopsis suspension culture. (A) EdU click reaction-based replication assay. Mild detection conditions without cell wall digestion or DNA digestion led to a better preserved cellular and nuclear morphology. Following 2 h 10 μM EdU incubation on 2d-old Arabidopsis culture, incorporated EdU was detected with click reaction using Alexa Fluor 488 azide (green). (B) BrdU-based replication assay on 2d-old Arabidopsis culture following 2 h 10 μM BrdU incubation. Harsh detection conditions resulted in partial loss of cellular and nuclear integrity. Alexa Fluor 488 antibody was used for immunodetection of BrdU (green). Nuclei were counterstained with DAPI and pseudocolored red. Arrows indicate nuclei with weak DNA staining. Differential interference contrast (DIC) transmission images were overlaid onto fluorescence images at the last panel. Scalebar: 10 μm.