Fig. 4. Distribution of intestine-expressed, intestine-, germ line- and muscle-enriched, and commonly-expressed genes on the C. elegans gene expression topomap. The gene expression topomap is an assembly of data from 553 microarray experiments in which genes that are strongly co-expressed are plotted in close proximity to each other on the map (Kim et al., 2001). The gray triangles represent all the genes in the topomap (17,817) and the red triangles represent the genes in each list.