Figure 2
Expression of Nar - ap during juvenile development. (A), (B), (N), (O), (Y), (Z) Ventral views, anterior to the top (but to the left in (Y), (Z)). (C-F), (H-M), (P-X) Dorsal views, anterior to the top (but to the left in (H), (I), (X)). (G) Lateral view, anterior to the left. (B), (O), (Z) Hoechst 33342 fluorescence ((B) is a different specimen than that shown in (A); (O) and (Z) are the same specimen as that shown in (N) and (Y), respectively). (J-M), (P-S), (T-V) Sets of contiguous focal planes (dorsal to ventral) of the head, which is outlined with dashes. Expression domains in this figure are indicated by the following symbols: arrowheads (black) ectoderm of nascent segments, arrowheads (white) presumed tegumentary neurons, arrows (large) dorsal mesoderm, arrows (small) medial cell clusters of the nerve cords, brackets brain, dashed ellipses palp bases, double arrowheads (black) pharynx, double arrowheads (white) lateral cell clusters of the nerve cords. (A-D) Hatchling stage. (A), (B) Anterior end. An asterisk marks the foregut lumen. (C), (D) Posterior end (same specimen; (C) is a Nomarski image and (D) is a brightfield image). (E) Mid 3-cheatiger stage, anterior end. (F), (G) Late 3-chaetiger stage. (F) Anterior end, out of focus and outlined with dashes. (H-M) 4-chaetiger stage. The posterior end is shown in (I), and dashed boxes in (K) delimit regions of eye development. (N), (O) 7-chaetiger stage. (P-S) 8-chaetiger stage. (T-W) 13-chaetiger stage. (X-Z) 17-chaetiger stage. (X) Notopodia of the 4 posterior-most chaetigers. (Z) Expression is false-colored red. ac anterior cirri, ae anterior eye, an antenna, ann antennal nerve, cp corpus pedunculus, ja jaw, p1 1st parapodium, pa palp, pe posterior eye, py pygidium, vnc ventral nerve cords.