Predicted to enable 3'-5' RNA helicase activity; mRNA binding activity; and single-stranded RNA binding activity. Involved in mRNA splicing, via spliceosome. Part of Prp19 complex. Is expressed in several structures, including central brain primordium; embryonic/larval midgut; embryonic/larval midgut primordium; ganglia; and larval nervous system. Orthologous to human AQR (aquarius intron-binding spliceosomal factor).