Fig. 4.

Rack1 deficiency decreases differentiation of crypt cells into enterocyte, goblet, and enteroendocrine cell lineages and promotes differentiation into Paneth cells. Immunofluorescent costaining for Rack1 (Rk1; green, panels at left) and the differentiation markers (red, panels at right) sucrase isomaltase (SI; A), synaptophysin (Syn; B), lysozyme (Lyso; C), or mucin-2 (Muc2; D and E) in the small intestine (A–D) or colon (E) of Rack1^−i/−i mice. DNA is labeled by Hoechst 33342 fluorescent staining (blue). Scale bar: 100 μm. Data are representative of up to 50 fields examined from 3 or more mice.