The authors wish to make readers aware of possible errors in J. Cell Sci. (2017) 130, jcs200329 (doi:10.1242/jcs.200329).
In early 2023, the authors sent the GFP–Sharpin plasmids used in the article for deposition at Addgene. Next-generation sequencing results provided by Addgene have revealed that the plasmid encoding the V240A/L242A point-mutant form of GFP–Sharpin also encodes an unexpected D293A mutation. The GFP–Sharpin V240A/L242A mutant plasmid was created as part of a previous study (De Franceschi et al., 2015; doi:10.1371/journal.pone.0143423), and sequencing of the plasmid at the time of that study did not identify the additional D293A mutation.
The authors do not know when the additional D293A mutation arose in the GFP–Sharpin V240A/L242A plasmid; therefore, it cannot be ruled out that the D293A mutation was present during all or some of the experiments using the GFP–Sharpin V240A/L242A construct that are reported in the article. It is also possible that the additional D293A mutation arose after the experiments were completed, as the plasmid has since been propagated.
The authors state that, because the experiments reported in Figs 2 and 4 of the article did not involve the GFP–Sharpin V240A/L242A construct, the conclusions that Sharpin interacts with the Arp2/3 complex and promotes lamellipodium formation are unaffected. However, the authors cannot rule out that the D293A mutation, rather than the V240A/L242A mutations, was responsible for disruption of the interaction between Sharpin and the Arp2/3 complex observed in experiments using GFP–Sharpin V240A/L242A (presented in Fig. 3 of the article). The authors further state that the rescue experiments assaying lamellipodium formation and cell migration using the GFP–Sharpin V240A/L242A mutant (presented in Figs 5 and 6 of the article) were performed after the interaction studies presented in Fig. 3. Thus, if the D293A mutation was present and contributed to the Arp2/3 interaction phenotype, it would also have been present during the rescue studies.