Figure 4

Expression of BfArnt . In situ hybridization of BfArnt with antisense probe and with sense probe. (A,B) No apparent expression is shown at the blastula stage. (C,D) BfArnt is ubiquitously expressed at mid gastrula stage. (E-H) Stronger BfArnt signals are detected in the dorsal part of the early neurula (arrow in G). (I-P) Beginning at mid-neurula stage, some regions of the central nervous system (CNS) specifically express BfArnt at a higher level. The CNS region showing the strongest expression (arrows) is next to the first somite, and this region seems to maintain the expression until two-day larva. Patches of weak expression are distributed in specific CNS cell clusters (arrowheads in I,K,M), but these patches fade when the embryos reach the larval stage. The scale bar applies to all panels. Blastoporal (bp) views and dorsal views (d) are labeled, and unlabeled panels are lateral views. In E, F, I-L, anterior is to the left; in M-P, anterior is to the upper left. Boundaries of somites are depicted in K.