Figure 3. Neurite branching on L1 substrates is impaired in L1¹¹⁵² mutant mice. A & I: WT; B & J: L1^Y1176A; C & K: L1¹¹⁸⁰; D & L: L1¹¹⁵².

A-D: Hippocampal neuronal culture grown on laminin substrate at 3 Days In Vitro (DIV). Neurons are stained with anti-tubulin. Total neurite length, longest neurite length, number of neurite branches and the number of neurites extending from soma are quantified. The mean values of neurons of L1CD mutant mice are normalized to mean values of neurons of L1^WT mice. *p < 0.05. Scale bar = 100 μm.

I-L: Hippocampal neuronal culture grown on L1-Fc substrate at 3 DIV. The number of neurite branches for L1¹¹⁵² mutant mice was significantly lower than L1^WT mice. *p < 0.05, **p < 0.001. The mean length or number of neurites on L1-Fc substrate was compared with the laminin substrate. Longest neurite length and neurite total length was increased more than two times, whereas number of branches of L1¹¹⁵² mice did not increase on the laminin substrate compared to L1^WT mice. *p < 0.05.