Fig. 1. Expression of c-Gcm1 in developing chicken embryonic CNS. c-Gcm1 in situ hybridization on whole chick embryos (A-D) and on transverse sections of embryonic spinal cord (E-G). (A,B) Dorsal views showing that c-Gcm1 expressing cells (purple) are detected in the anterior neural plate at stage 4, in an area corresponding to the epiblast as shown on transverse section in A'. (B) Colabeling shows that c-Gcm1-expressing cells are included in the Sox2 expression domain (red). (C) During neurulation, c-Gcm1 is strongly expressed throughout neural tube and neural plate. (D,E) Starting from E1.5 (stage 11), c-Gcm1 is expressed in the neural tube (D), along the entire dorsoventral axis except in the dorsal-most region (E). (F) At E2.5 (stage 14), c-Gcm1 expression is downregulated in neural progenitors lining the lumen whereas it is maintained in cells located in the newly formed intermediate mantle layer. (G) At E8 (stage 34), c-Gcm1 RNA is no longer detected in the spinal cord. hn, Hensen's node; ps, primitive streak. Scale bars: 60 µm in E; 70 µm in F; 150 µm in G.