Fig. 2

Alterations of cortical neuronal distribution in Fmr1 KO mice. a Immunohistochemistry with Cux1, a layer II/III-specific protein marker, and Ctip2, a layer V-marker is performed in WT and Fmr1 KO mice. Regions of interest (ROIs) are positioned over the neocortex with each ROI further subdivided into eight equal bins spanning the pia to the inner border of the cortex, to assess neuron distribution in different cortical layers. The number of Cux1⁺ and Ctip2⁺ cells are counted in each bin and expressed as a percentage total numbers. Scale Bar: 100 μm. b The proportion of Cux1-labeled cells is significantly lower in bin 3 near superficial layers II/III, along with a corresponding increase in deeper layers of bins 5, 6, 7 and 8 for KO mice relative to WT (n = 24–32 per group). c As for Ctip2, there is a larger proportion of cells positioned in bin 3 but less in deeper layer bin 5 of KO mutants when compared to controls (n = 30–32 per group). Data are presented as mean ± SEM. *p < 0.05, **p < 0.01