VOLUME 285 (2010) PAGES 33529–33539
The authors recently became aware that Fig. 6 contained a duplication of the protein blots shown in the lower frames of panels of Fig. 6, B and C. This inadvertent error was made when the final figure was assembled for publication; the lower frame in C in the published paper is incorrect. Upon becoming aware of this error, we returned to the original unedited data files from these experiments in order to replace the incorrect frame with the correct image. This correction has no effect on the results and the conclusions drawn. We apologize to the community for any confusion this may have caused.