Orphan nuclear receptor (Probable). Plays a role in morphogenesis and elongation during embryonic and larval development (PubMed:16920335). Plays a role in muscle formation and motility (PubMed:16920335, PubMed:18616929). Isoform b: Expressed in body wall muscle cells, pharyngeal muscles, rectal gland cells, vulval and uterine muscles and neurons in the head and ventral nerve cord (PubMed:16920335). Isoform c: Expressed in body wall muscle cells, neurons in the head, nerve ring, ventral and dorsal nerve cords and epidermal cells in the tail (PubMed:16920335). Expressed throughout development (PubMed:16920335). First expressed in embryos from the 1.5-fold stage (PubMed:16920335). Highly expressed during the L2 stage of larval development (PubMed:16920335). RNAi-mediated knockdown results in arrest due to elongation and morphogenesis defects at the embryonic or larval stages in 30% of offspring (PubMed:16920335). Furthermore, embryos have highly disorganized epithelial cells (PubMed:16920335). RNAi-mediated knockdown in adults results in mis-localized or missing body wall muscle cells (PubMed:16920335). Belongs to the nuclear hormone receptor family.