In the article “Membrane-Tethered Monomeric Neurexin LNS-Domain Triggers Synapse Formation,” by Ozgun Gokce and Thomas C. Südhof, which appeared on pages 14617–14628 in the September 4, 2013 issue, representative cell images in Figures 4A and 5B were duplicated during final figure assembly. The second column of Figure 4A and the second and fourth columns of Figure 5B have been updated. The corrected figures appear below. These errors do not affect the conclusions of the paper.
