|
Fig. 4 Expression of ptc1 and shh in cyclops mutants. ptc1 expression is detected in blue (A,B) or in red (C,D) and shh in blue (C,D). (A) Frontal view of embryos at the 1- to 2-somite stages. Expression of ptc1 is shown in a wild-type sib on the left and in a cyclops mutant on the right. To provide a landmark along the anteroposterior axis, embryos were simultaneously hybridized with a probe for pax-2 highlighting the position of the future posterior midbrain (asterisk). (B) ptc1 expression in a 24-hour-old cyclops mutant. The arrowhead indicates re-expression of ptc1 at high levels in a dorsoventral stripe in the diencephalon. (C) 24-hour-old cyclops embryos. ptc1 expression is revealed in red, shh in dark blue. (D) 24- hour-old wild-type embryo.