Expression of TeNT-LC caused a failure of maintenance of callosal axons in the contralateral somatosensory cortex. A–F , After expression of TeNT-LC in layer II/III cortical neurons ( A , C , E ), their axons in the contralateral cortex were greatly reduced at P12 ( B ) and P14 ( D ) and almost completely lost at P21 ( F ). For comparison with normal callosal projections, see Figure 1. Ipsi, Ipsilateral side to electroporation; Contra, contralateral side to electroporation. Scale bar, 500 μm.