Fig. 8

Overexpression of Pitx can activate Lhx3 expression and inhibit the expression of FoxE4 and Nkx2.1. a–f These control groups are not injected with Pitxc mRNA. a’–e’ These groups are injected with Pitxc mRNA at the unfertilized egg stage. b’–f” Pitxc mRNA is injected into one blastomere at 2-cell stage. Red boxes indicate the region in which FoxE4 or Nkx2.1 expression disappeared. The black arrows indicate left preoral pit marked by Lhx3 and red arrows indicate the new induced preoral pit. The embryos detected is at N1 stage in (a, a’, c, c’), N2 stage in b–b”, d–d”, f–f”, N4 stage in e, e’. Numbers in the bottom right comer of a panel show the number of times in phenotype was observed in total number of embryos examined. The remaining injected embryos not shown showed similar gene expression patterns like the uninjected embryos. All the images are dorsal view. A, anterior; P, posterior; L, left side; R; right side. Scale bars: 50 μm