Fig. 2. Comparison of Math1 and Zic protein expression. Double immunofluorescence labelling with antisera against Zic factors (green) (A,C) and Math1 (red) (B,C) in cross-sections of mouse E10.5 dorsal neural tube. (D-F) Higher magnification images of the region comparable with the boxed region in C. The region of lowest Zic expression (A,D, arrows) is the region where Math1 is expressed in the dorsal neural tube (C,F). Note that the cells expressing highest levels of Math1 do not express Zic factors. Cells expressing low levels of both factors are detected (arrowheads). (G) Zic factor immunofluorescence in E10.5 Math1 mutant dorsal neural tube. Note the uniform Zic expression when compared with wild type (D). Scale bar: 100 µm in A-C; 35 µm in D-G.