Nature 465, 492–496 (2010)

In our recent Corrigendum (Nature 471, 254 (2011); doi:10.1038/nature09897), Fig. 4g inadvertently contained three incorrect panels. The corrected Fig. 4g is shown below. This mistake does not alter the overall conclusions of this Letter.

Figure 1
figure 1

This is the corrected Fig. 4g.