Probable ATP-dependent RNA helicase involved in RNAi-mediated gene silencing (PubMed:24684930, PubMed:24684931). Specifically required in the endogenous siRNA pathway for biogenesis of secondary endogenous small interfering RNA (siRNA) intermediates called 22G-RNAs (PubMed:24684930, PubMed:24684931). May associate with and recruit rde-10 to primary siRNA-targeted mRNA for secondary siRNA synthesis (PubMed:24684930). May be recruited to target mRNAs by rde-1 and/or ergo-1 (PubMed:24684930, PubMed:24684931). ATP + H2O = ADP + H(+) + phosphate Interacts with wago-1, ergo-1 and rde-1. Colocalizes with pgl-1 in perinuclear P granules. Colocalizes with rsd-6 in a subset of germline and embryonic foci. Expressed in the soma and germline. The C-terminal region is necessary for localization to P granules. Viable with no obvious developmental defects. Insensitive to RNAi-mediated gene silencing. Increased sensitivity to viral infection. Belongs to the DEAD box helicase family. DDX3/DED1 subfamily.