Acts late in the splicing of pre-mRNA. Mediates the release of the spliced mRNA from spliceosomes. ATP + H2O = ADP + H(+) + phosphate Belongs to the CWC complex (or CEF1-associated complex), a spliceosome sub-complex reminiscent of a late-stage spliceosome composed of the U2, U5 and U6 snRNAs and at least BUD13, BUD31, BRR2, CDC40, CEF1, CLF1, CUS1, CWC2, CWC15, CWC21, CWC22, CWC23, CWC24, CWC25, CWC27, ECM2, HSH155, IST3, ISY1, LEA1, MSL1, NTC20, PRP8, PRP9, PRP11, PRP19, PRP21, PRP22, PRP45, PRP46, SLU7, SMB1, SMD1, SMD2, SMD3, SMX2, SMX3, SNT309, SNU114, SPP2, SYF1, SYF2, RSE1 and YJU2. Present with 907 molecules/cell in log phase SD medium. Belongs to the DEAD box helicase family. DEAH subfamily. DDX8/PRP22 sub-subfamily.