GFP was expressed in the pharynx, intestine, hypodermis and body wall muscles, in L1 through adult stages. In the head, GFP was seen in neurons of the lateral, vesicular and retrovesicular ganglia. Ventral cord neurons also were visible, as was the PVT neuron, but only two phasmid neurons were detected in the tail. Whereas the nervous system is the primary site of gfp expression mediated by the
daf-1 promoter, the
daf-4 promoter directs expression more broadly, consistent with its other functions. In L1 larvae, when the dauer/nondauer decision is made,
daf-4 promoter is active in neurons in the head, as well as in the ventral cord and tail. The promoters continues to express GFP in dauer larvae from starved plates.