Earliest expression with the antibody was seen in a small cluster in late-gastrulation embryos. From their position, these cells may be the precursors of the pharyngeal cells that express GFP in the L1 larva.
ceh-2 expression was found restricted to eleven cells (fourteen nuclei) of five types in the anterior pharynx (corpus) of larvae and adults: the I3 neuron that lies embedded in the dorsal sector of the pharynx muscle; the pairs of NSM and M3 motoneurons in the left and right subventral sectors; the three
m2 muscle cells, each possessing two nuclei resulting from cell fusion during development; and the three
e2 epithelial cells with the anterior-most pharynx nuclei.