After publication of our recent article , we noticed that this study was initiated in Qian Chen's lab and that we had inadvertently omitted Qian Chen as a co-author. The study was also supported by other grants from NIH. Revised acknowledgment and authors' contribution paragraphs appear below.
The author list is now complete and the competing interests section modified accordingly.
The authors declare that they have no competing interests.
FW participated in the study design, wrote most of the manuscript, performed most of the experiments and analyzed data. DCM, GZ, YL, XW, and JKL participated in the study design, data interpretation and revised the manuscript critically. LW and QC conceived the study, participated in its design, data analysis and revised the manuscript carefully and critically. All authors have read and approved the final manuscript.
We would like to thank Dr Jason T Machan for statistical analysis support, Dr R Terek provided samples, and Dr ZK Wang for his suggestion. This project was supported by NIH AR052479, R01AR059142, AG14399, AG00811, P20RR024484 by grants from the Aircast Foundation, Arthritis National Research Foundation, NSFC 81071495, 81171676, and SXNSFC 2011011042.