Almost every transgenic animal shows strong DAF-3/GFP expression in many, but not all, head neurons, the ventral nerve cord (both cell bodies and processes), the intestinal cells, especially the membrane adjacent to the intestinal lumen, and tail hypodermal cells and neurons. Weak expression in the pharynx, hypodermal V blast cells, P blast cells and
hyp7 hypodermal cells is observed in about half of the transgenic animals. Expression in the tail hypodermal cells hyp 9, hyp 10, and hyp 11 is clearly seen in nearly every animal. This apparent difference between tail hypodermal expression and main body expression may be a consequence of the anatomy of the animal. The main body hypodermis is underlain by bright GFP in the intestine and ventral nerve cord, so weak expression in the hypodermis is hard to see against this background. Expression is rarely detected in dorsal body wall muscle. DAF-3/GFP is expressed in the distal tip cells and in their precursors, Z1.a and Z4.p, throughout development. DAF-3/GFP is also expressed strongly in unidentified vulval cells in adults. In wild-type embryos of 200 to 400 cells, DAF-3/GFP is expressed uniformly thoughout the embryo.