Wnt proteins that activate β-catenin signaling increase presynaptic inputs. (A, C, E) Representative images of control (A, C, E, left), Wnt3a (A, right), Wnt7a (C, right), or Wnt7b (E, right) treated cultures immunostained with Vesicular glutamate transporter 1 (VGLUT1; green) and Microtubule associated protein 2 (MAP2; dark blue). Cultures were treated for 36 hours and stained at 10 days in vitro (10 DIV). The same concentrations of proteins were used as in Figure 4. Scale bar = 2 μm. (B, D, F) Quantification of the number of VGLUT1 puncta per area of dendrite for Wnt3a (B; n = 79 fields of view; **p < 0.001, Students t-test), Wnt7a (D, n = 59 fields of view; **p = 0.05, Students t-test), or Wnt7b (F; n = 82 fields of view, **p < 0.001, Student's t-test) treated cultures. All conditions were normalized to control. Error bars represent SEM. (G) Representative images of control (left) and Dkk-1 (right; 1 μg/mL) treated cells stained with VGLUT1 (green) and MAP2 (dark blue) at 14 DIV after 48 hours of treatment. Scale bar = 2 μm. (H) Quantification of the number of VGLUT1 puncta per area of dendrite (± standard error of the mean). Dkk-1 treatment was normalized to control treatment. (n = 80 fields of view, *p < 0.01, Students t-test).