Involved in pre-mRNA splicing. Required for the export of mRNA out of the nucleus. ATP + H2O = ADP + H(+) + phosphate Binds ALYREF/THOC4 and DDX39B/BAT1. Interacts with SARNP. Interacts with human cytomegalovirus/HHV-5 protein UL69. Interacts with MX1. Interacts with MCM3AP isoform GANP (PubMed:23652018). Can translocate to the cytoplasm in the presence of MX1. Detected in testis, and at lower levels in brain, kidney, lung, thymus, spleen and salivary gland. Up-regulated in proliferating cells. Present at low levels in quiescent cells. Probably devoid of RNA helicase activity. Probably devoid of RNA helicase activity. Belongs to the DEAD box helicase family. DECD subfamily. Extended N-terminus.