Background：

DEAD box proteins， characterized by the conserved motif Asp-Glu-Ala-Asp (DEAD)， are putative RNA helicases. They are implicated in a number of cellular processes involving alteration of RNA secondary structure such as translation initiation， nuclear and mitochondrial splicing， and ribosome and spliceosome assembly. Based on their distribution patterns， some members of this family are believed to be involved in embryogenesis， spermatogenesis， and cellular growth and division. This gene encodes a DEAD box protein， which has an ATPase activity and is a component of the survival of motor neurons (SMN) complex. This protein interacts directly with SMN， the spinal muscular atrophy gene product， and may play a catalytic role in the function of the SMN complex on RNPs.