Figure 2

Figure 2

Notch pathway activity is required for spinal cord morphogenesis. (a,b) mib1 loss of function prevents DlA internalization (n = 9). (c,d) Combined inactivation of dld and dla disrupts apico-basal polarity in 9/10 embryos. (e,f) The γ-Secretase inhibitor LY411575 disrupts apico-basal polarity (n = 18). (g,h) Similarly the γ-Secretase inhibitor DAPT perturbs polarity in 4/5 embryos. (i-l) RNA injection of a constitutively activated form of Notch (NICD) restores neuro-epithelial morphology and apical aPKC localisation (k) but not DeltaD endocytosis (l) in 22/22 mib1 mutant embryos. (m,n) Polarity defects are observed in 20/46 embryos injected with RNA encoding dominant-negative Su(H) (DN-Su(H)). (o,p) RNA injection of constitutively activated Su(H) (CA-Su(H)) restores apico-basal polarity in 17/17 mib1 mutants. All images are dorsal views of the anterior spinal cord, anterior left. (a–f) 22 somites stage, (g,h,m,n) 30 somites stage, (i–l,o,p) 16 somites stage. Scalebars: 20 µm.