Figure 4.

Expression of the chicken olfactory receptor gene family in the notochord. (A) Coronal sections (14 μm) of the neural tube (nt) and the notochord (n) at E5 were stained with toluidine blue. (B) Adjacent sections were hybridized with an antisense RNA probe from the chicken Sonic Hedgehog (cSHH) used as a marker of the notochord and of the floor plate (f). (C–H) Serial adjacent sections were hybridized with antisense RNA probes prepared from all the known members of the COR gene family: COR1–6 (C), COR7ab (D), COR8 (E), COR9 (F), COR10 (G), and COR11 (H). Note that positive signals were detected only with the COR7ab probe. (I) Higher magnification of a region (arrow in D) of the notochord labeled with the COR7ab antisense RNA probe. [Bars = 34 μm (A–G) and 5 μm (I).]