The C. elegans intestine is a bilaterally symmetric tube of 20 polarized epithelial cells. Cell polarity in the intestine involves a reorganization of the microtubule cytoskeleton, followed by migration of the intestinal nuclei apically, and other organelles basally. Small apical membrane separations coalesce into a continuous compartment to form the lumen of the intestine. Cell ablation experiments suggest that morphogenesis of the intestine requires interactions between intestinal cells and interactions between intestinal and non-intestinal cells surrounding the intestine 1,2 . We have been conducting screens for embryonically-expressed genes required for intestinal morphogenesis, and are currently characterizing one mutant,
zu450 , in more detail. The intestines of
zu450 homozygotes appear slightly disorganized, and have abnormally wide intestinal lumens. Analysis of
zu450 intestines using two indicators of epithelial polarity, the adherens junction marker MH27 and the lumenal marker MH33, reveal defects in the attachment of the intestine to the pharynx and rectum as well as discontinuities in the intestinal lumens. Preliminary analysis of the mutation
zu450 suggests that it may play a role in multiple epithelia;
zu450 homozygotes have elongation and enclosure defects in addition to intestinal morphogenesis defects. 1 Leung, B., G. J. Hermann, and J. R. Priess (1999). Developmental Biology 216 : 114-134. 2 Hermann, G. J., B. Leung, and J. R. Priess (2000). Development 127 : 3429-3440.