Fig. 1.

CPG15 induction by kainic acid and its expression in Xenopus optic tectum. (A) Immuno-blot of protein extracts from tadpoles harvested at the specified times after intraventricular injection of KA, or rat hippocampus dentate gyri 24 hours after ip injection of KA (right lane). Incubation with the antiserum to CPG15 labels a 12-kD band (arrow) that is not seen with preimmune serum (PI). Confocal images of sections through the optic tecti of untreated tadpoles (B and C) or tadpoles infected with CPG15VV (D and E) or CPG15t3VV (F and G). Sections probed with preimmune rabbit serum show no specific labeling (B). Outlined on this section are the optic tectal neuropil (N), differentiated tectal neurons (TN), and the proliferative zone (PZ). These same regions can be discerned in the sections stained with the antisera to CPG15 [(C), (E), and (G)]. A honeycomb pattern of endogenous CPG15 immunoreactivity can be seen in the TN region of the tectum, and retinal ganglion cell axons are stained in N (C). Sections from animals infected with virus were double-labeled with anti– β-gal to show extent of infection [(D) and (F)] and with anti-CPG15 at higher magnification [(E) and (G)]. In the infected tecti [(E) and (G)], the honeycomb pattern of CPG15 immunoreactivity also extends into the PZ, where many infected neurons are located [(D) and (F)]. Arrows mark retinotectal axons. Bar, 100 μm for upper panel and 50 μm for lower panels.