||Figure 4 Whole-mount in situ hybridization demonstrates the developmental expression of xKv3.1 transcripts. Top row: lateral views reveal mRNA is not detected in the neural plate of
gastrula stage (E15) embryos; however, it is expressed in the spinal cord and brain at early neural tube stages (E22). The signal increases and extends caudally in the spinal cord in stage 27 and 35 embryos. Anterior is to the right in all views. E15, dorsal view; E22-35, lateral views and dorsal up. Bottom row: at the 2-day larval stage (E39) xKv3.1 transcripts fully span the entire length of the spinal cord. A dorsolateral view reveals two parallel rows of labeled neurons that divide anteriorly (E32). Scale bar top row: 0.75, 0.70, 0.85, and 1.3 mm; bottom row: 1.5 and 0.6 mm.