Probable ligand of isoforms a and b of the calcitonin receptor-like protein, pdfr-1, a G-protein coupled receptor (PubMed:18390545). May not signal through isoform c of pdfr-1 (PubMed:18390545). Involved in locomotion; may play a role in circadian rhythms of locomotor activity (PubMed:18390545, PubMed:22579613, PubMed:26113231). Modulator of egg-laying (PubMed:22579613). Expressed in the interneurons BDUL/R, AVG, AIML/R, RIS, AVD and PVT, the chemosensory neuron pairs PHA and PHB, the motor neurons RID and RIML/R, the sensory neurons AQR and PQR, and in the PVPL/R interneurons (PubMed:19686386). Also expressed in rectal gland cells rectD and rectVL/R, the intestino-rectal valve cells virL/R and three posterior arcade cells in the head (PubMed:19686386). Delay in the timing of the reproductive peak of egg-laying.