Anti-Pax6 perturbs early Pax6 expression in the eye territory. (a-i) Pax6 (a-c and g-i') or Rx3 (d-f) in situ hybridization (ISH). Zebrafish embryos were injected at the blastula stage with vehicle (phosphate-buffered saline (PBS) in (a,d,g,g',j) or monoclonal anti-Pax6 (b,c,e,f,h,i,h',i'). (g'-i') Lower magnification versions of (g-i). Arrows indicate symmetric (black) and asymmetric (blue) distributions. ISH was performed at 0 to 3 somites (a-f), or 15 to 18 somites (g-i'). (j-l) Eye fields were photographed on live embryos at about 10 somites, after injection at the blastula stage with PBS (j) or monoclonal anti-Pax6 (k,l). d, diencephalon; h, hindbrain; a, anterior; p, posterior. N = 36 (a); n = 97 (b,c); n = 25 (d); n = 144 (e,f); n = 23 (g); n = 43 (h,i); n = 25 (j); n = 48 (k,l).