Fig. 8

Fig. 8 Expression of anterior midline markers in ethanol-treated embryos. (A and B) Control (A) and ethanol-treated embryos hybridized to hgg-1 (hg) and pax-2 (p) probes. (C and D) otx-2 expression in control (C) and ethanol-treated embryos (D) stained with otx-2 probe. Arrow indicates otx-2 expression in the posteriorly displaced prechordal plate in the ethanol-treated embryo (D). (E to G) Control (E) and ethanol-treated embryos (F, G) labeled with isl-1 (i) and pax-2 (p) probes. (H to L) Control (H) and ethanol-treated embryos stained with hlx-1 (h) and pax-2 probes (p). hlx-1 expression is impaired anterior to the pax-2 expression domains, but unlike hgg-1 (B) and isl-1 (C) hlx-1 transcripts are not detectable posterior to the pax-2 stripes (L, arrowhead). (M to P) Control (M) and ethanol-treated embryos (N to P) stained with shh (s) and pax-2 probes (p). Ethanol-treated embryos show progressive loss of anterior shh expression, while expression of shh posterior to the pax-2 stripes is unaffected in treated embryos. Embryos are at the 100% epiboly stage and are shown in dorsal views with anterior up.