Here’s the notice for the paper, which has been cited 23 times, according to Thomson Scientific’s Web of Knowledge:
Retraction for “Structural basis for nucleotide exchange on Gαi subunits and receptor coupling specificity,” by Christopher A. Johnston and David P. Siderovski, which appeared in issue 6, February 6, 2007, of Proc Natl Acad Sci USA (104:2001–2006; first published January 30, 2007; 10.1073/pnas.0608599104).
The authors wish to note the following: “In our paper, a cocrystal structure at 2.2 Å resolution was described of the heterotrimeric G-protein alpha subunit Gαi1 bound to two peptides: one from an artificial sequence that promotes nucleotide exchange (KB-752) and a second peptide (D2N) from the third intracellular loop of the D2 dopamine receptor (PDB ID code 2HLB). Further examination of the unbiased electron density map has revealed that, while electron density exists for the KB-752 peptide, there is a lack of clear and continuous electron density for the D2N receptor peptide in the complex. Because the structural model represents a major conclusion of the paper but is unsupported by the experimental electron density map, we wish to retract the paper. Both authors deeply regret this mistake and sincerely apologize.”
The reason for the retraction is essentially the same as the one for the Structure paper. We’ve contacted Siderovski for comment, and will update with anything we hear back.
Siderovski has collaborated with the late Maria Diverse-Pierluissi, four of whose papers were retracted after her death. Siderovski and Diverse-Pierluissi published two papers together, neither of which has been retracted — although a former postdoc in Diverse-Pierluissi’s lab suggests there may be issues with one of them. And Mount Sinai, where Diverse-Pierluissi worked, told us several months ago that they considered their investigation closed.
In other words, we have no reason to think the retractions are related. But this seems to be the first case of two groups linked by disparate retractions.
Update, 2 p.m. Eastern, 1/26/12: It turns out we missed a correction by the same group that was released the same day in PNAS — and for basically the same reason as the retraction:
Correction for “Regulators of G-protein Signaling accelerate GPCR signaling kinetics and govern sensitivity solely by accelerating GTPase activity,” by Nevin A. Lambert, Christopher A. Johnston, Steven D. Cappell, Sudhakiranmayi Kuravi, Adam J. Kimple, Francis S. Willard, andDavid P. Siderovski, which appeared in issue 15, April 13, 2010, of Proc Natl Acad Sci USA (107:7066–7071; first published March 29, 2010; 10.1073/pnas.0912934107).
The authors note that Fig. 1 appeared incorrectly. They also wish to note the following: “Upon further evaluation of the unbiased electron density maps for the structural models of Gαi1(G202A)·GDP (PDB id 2PZ2) and Gαi1(G202A)·GDP·AlF4–(PDB id 2PZ3), there is a lack of clear and continuous density to support an entirely ordered switch II region or to support the presence of aluminum tetrafluoride in the latter structure. We have therefore obsoleted the x-ray structure model PDB 2PZ3 from the Protein Data Bank. We have replaced PDB 2PZ2 with PDB 3UMS in the Protein Data Bank to reflect the more accurate refinement of the Gαi1(G202A)·GDP structural model.”
The corrected figure and its corresponding legend appear below. This error does not affect the conclusions of the article.
Hat tips: Clare Francis, Vladimir Svetlov