Is an ortholog of human CELF5 (CUGBP Elav-like family member 5). Exhibits single-stranded RNA binding activity. Is involved in several processes, including cholinergic synaptic transmission\; modulation of chemical synaptic transmission\; and regulation of alternative mRNA splicing, via spliceosome. Localizes to the nuclear speck. Is expressed in the nervous system and the pharyngeal gland cell.