Probable ATP-dependent RNA helicase. Component of the nucleolar ribosomal RNA (rRNA) processing machinery that regulates 3' end formation of ribosomal 47S rRNA (PubMed:25825154). ATP + H2O = ADP + H(+) + phosphate Associates with PeBoW complex, composed of BOP1, PES1 and WDR12 (PubMed:25825154). Interacts directly with BOP1 and PES1 (PubMed:25825154). Associates with 60S and 90S pre-ribosomal particles (PubMed:25825154). The C-terminal domain regulates nucleolar localization (PubMed:25825154). Belongs to the DEAD box helicase family. DDX27/DRS1 subfamily. It is uncertain whether Met-1 or Met-32 is the initiator. Sequencing errors. Truncated N-terminus. Truncated N-terminus. Truncated N-terminus.