GFP expression was observed in the head and the developing ventral nerve cord beginning in mid-stage embryos and continuing into adulthood. In the head, GFP was detected in more than twenty neurons in the anterior, lateral, ventral and retrovesicular ganglia. Fluorescent processes terminating at the tip of the head suggest that
daf-1 is expressed in sensory neurons and in support cells in the amphids and inner labial sensilla. In the midbody, GFP was expressed in the ALM mechanosensory neurons and the PVT neuron, as well as one additional neuron pair. In the lumbar ganglia of the tail, five cells expressing GFP included phasmid neurons and PLN and PLM mechanosensory neurons. The
daf-1 promoter also conferred gfp expression in nonneuronal cells, including a membranous sheath surrounding the distal end of the intestine and in the distal tip cell (DTC) of the gonad. In some lines, GFP was sometimes detected in the muscles of L4 and adult animals. In L1 larvae,
daf-1 promoters is active in neurons in the head, as well as in the ventral cord and tail. The promoter continues to express GFP in dauer larvae from starved plates.