Fig. 11.

Model of cell-cell adhesion during organogenesis of the C. elegans intestine. Genetic data suggests that in the intestine at least two redundant cell-cell adhesion systems (1 and 2) are involved in apical junction and lumen formation, which both act at the level of cell adhesion molecules, linker proteins and cytoskeletal organizers (note that only the phosphorylated form of SAX-7, SAX-7P, localizes at the CeAJ) (Chen et al., 2001). At the core of each system, linker proteins and cytoskeletal organizers strongly interfere with the localization of cell-cell adhesion molecules and IFs/AFs, respectively, but in both systems these molecules are not predominantly required for each other’s localization (e.g. ERM-1 and the DAC still localize apically in ifo-1(kc2); see Fig. 9I, Fig. 10B-B″ and Discussion).