Nucleic Acids Research, Volume 36, Issue 5, 1 March 2008, Pages 1713–1722, https://doi.org/10.1093/nar/gkn014
The Editors were alerted in July 2022 about potential issues with Figures 2A, 2C and 6A as detailed below.
Figure 2A: There appear to be signs of splicing and potential background duplication.
Figure 2C: There appears to be a rectangle lighter than the general background around the central band in the GST-p21 lane.
Figure 6A: PCNA lanes 3 and 6 appear to be similar after horizontal flip.
The editors subsequently investigated, liaised with the authors, and have concluded the following.
Figure 2A
Below is published Figure 2A after Gradient Map adjustment. The black arrow indicates a clear splice line. The grey arrows indicate potential splice lines. The white arrows indicate two areas with unusual level of similarity.
The authors no longer have the original data used to generate Figure 2A. They have provided the result of a contemporaneous replicate experiment, shown below (at two different exposure times). The Editors conclude that the image was manipulated to conceal non-specific bands and Figure 2A is not a reliable representation of the results. However, the replicate experiment confirms the validity of the results.
Figure 2C
The authors have provided the original Coomassie gel used in Figure 2C, shown below, confirming the results. The red box indicates the region of the gel used in Figure 2C. The Editors believe the lighter rectangle around the band is a jpeg compression artefact.
Figure 6A
Below is published Figure 6A after Equalize (top) and Gradient Map (bottom) adjustments. The grey arrows indicate potential splice lines. Bands 3 and 6 in the middle panels are identical after horizontal flip.
The authors no longer have the original data used to generate Figure 6A. They have provided the result of a contemporaneous replicate experiment, shown below (in red box). The Editors concluded that the image was manipulated by duplicating lanes 3 and 6 in the original image. Figure 6A is not a reliable representation of the results. However, the replicate experiment broadly confirms the result that increasing quantities of GST-p21 decreases binding of PCNA to p300.
In conclusion, while these issues may not affect the results or conclusion of the study, in the absence of original data, the Editors advise readers to examine Figures 2A and 6A with care.
Julian E. Sale, Barry L. Stoddard
Senior Executive Editors