Figure 3.

Celsr2 knockout contributes to neurite growth in primary spinal motor neuron culture. (A and B) E13.5 spinal motor neurons from Celsr2^+/+ (A) and Celsr2^–/– (B) mouse embryos were cultured for 6 DIV and immunostained for Tuj1 (red). DAPI counterstained nuclei (blue). (C and D) Double immunostaining of cultured neurons for F-actin (blue) and Tuj1 (red) disclosed the axon shafts and growth cones. (E and F) Statistical analysis of total neurite length (E; control: 165.25 ± 10.52 μm, mutant: 354.19 ± 24.89 μm; P < 0.0001, n = 41 in the control and n = 36 in the mutant) and growth cone areas (F; control: 17.48 ± 0.91 µm², mutant: 84.89 ± 7.75 µm²; P < 0.0001, n = 58 in the control and n = 40 in the mutant). (G) Protein extracts from E13.5 ventral horns of cervical spinal segments was subjected to western blots using anti-EB3 and β-III tubulin (tubulin). There was a dramatic increase of EB3 in the mutant compared to the control (control: 0.99 ± 0.09, mutant: 1.35 ± 0.01; P < 0.05, n = 3 animals in each group). *P < 0.05; ****P < 0.0001; Student’s t-test.