Nan Yao and Jean T. Greenberg (2006). Arabidopsis ACCELERATED CELL DEATH2 Modulates Programmed Cell Death. Plant Cell 18: 397–411.
Due to an error made in archiving the data on one particular day when repeating electron microscopic–terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (EM-TUNEL) experiments, the authors provided an incorrect panel for Figure 1L. EM-TUNEL is a method for detecting DNA fragmentation that results from apoptotic signaling cascades. It was originally reported that infection of Arabidopsis with Pseudomonas syringae pv maculicola strain DG6 induces chromatin condensation (heterochromatin) accompanied by EM-TUNEL–positive staining indicative of programmed cell death. The authors believe the original conclusion is correct after examining old data from replicate experiments and repeating the experiments. The accompanying figure replaces Figure 1L. In the top panel, a part of a nucleus (N) with heterochromatin (Hc) shows a high density of gold particles, indicating that the heterochromatin region is TUNEL-positive 18 h after infection with strain DG6. A portion of a chloroplast (Ch) is also shown. In the bottom panel, the density of gold grains is quantified (n = 25) in mock-treated (10 mM MgSO4) control tissue or infected tissue. Different letters in the bar graph indicate that values are different using Student's t test (P < 0.001). The data confirm that infection causes significantly increased TUNEL staining, a reaction that required the presence of the terminal deoxynucleotidyl transferase enzyme (TdT).
Figure 1.
