Fig. (5) Sec23a ubiquitylation affects COPII vesicles formation. Huh7 cells seeded on glass coverslips were transiently transfected with the wilde type Sec23a-GFP or the mutated isoforms (C432A-Sec23a-GFP or C449A-Sec23a-GFP) and after 48 h of transfection processed for immunofluorescence with Sec16 specific antibody. The mean number of Sec23a-GFP positive spots (mean ± SD) and the percent of Sec23a-GFP pixels colabeling with Sec16a pixels (mean ± SD) are reported in the Sec23a-GFP panels and in the merged panels respectively.