Fig. 5. Ectopic p27^Xic1 promotes primary neurogenesis. Embryos were injected with (A) 45 pg p27^Xic1 and ßgal (light blue, injected side towards the left) and analysed at stage 15 for BrdU incorporation. Embryos were injected with (B) 60 pg p27^Xic1, (D) 30 pg p27^Xic1 NT, (E) 50 pg p27^Xic1 CT or (F) 50 pg p27^Xic1 35-96 with ßgal and analysed at stage 15 for Nßtub expression (purple) by in situ hybridisation. Dorsal views show that p27^Xic1 (B) and p27^Xic1 NT (D) induce ectopic neurones within the neural plate (arrows), whereas p27^Xic1 CT (E) and p27^Xic1 35-96 (F) have no effect. (C) A section of a stage 15 embryo injected with 45 pg p27^Xic1 indicating cell-autonomous Nßtub upregulation by p27^Xic1. (G) Western blot for p27^Xic1 levels on stage 10.5 embryos injected with increasing doses (30-150 pg) of p27^Xic1 RNA.