In adult animals, expression was seen in three distinct areas: in the eight vulval muscles, in 8-10 ventral neurons in the head and in the most posterior pharyngeal muscle cell,
m8. Expression in vulval muscle cells was seen from the L4 larval stage onward, starting just before these cells began contractile activity. Vulval muscle cells are born in the late L3 larval stage. Two sex myoblast cells present in the L3 larval stage are the precursors to the eight vulval and eight uterine muscles. No
ceh-24 reporter activity was seen in the sex myoblasts or uterine muscles. Expression in the pharynx was limited to a single cell, the donut-shaped muscle cell
m8. This unique cell forms the rear of the pharynx.
m8 expression was first seen in the embryo, beginning approximately 400 minutes after the first cell cleavage. This activity continued throughout the life of the animal. The
ceh-24 reporter construct was active in SMDVL, SMDVR, SIBVL, SIBVR, SIBDL and SIBDR. There are another four neurons with
ceh-24 promoter activity appear to belong to the SI/SM class of sublateral neurons.