Involved in translational control mechanisms operating in early stages of oogenesis. Required maternally in many stages of oogenesis, including cystocyte differentiation, oocyte differentiation, and specification of anterior-posterior polarity in the developing cysts. Essential for the formation and/or structural integrity of perinuclear nuage particles during germ cell formation. Required for gus, Fsn and aub accumulation at the posterior pole of the embryo. Required for the localization of vas to the perinuclear region of nurse cells. ATP + H2O = ADP + H(+) + phosphate Interacts with eIF5B and faf. Interacts with gus (via B30.2/SPRY domain) and Fsn (via B30.2/SPRY domain). Interacts with aub, me31B, eIF-4a and TER94. Interacts with piwi; this interaction is RNA independent. Interacts with Dcr-1 and Fmr1; these interactions occur in the polar granules. Component of the meiotic nuage, also named P granule, a germ-cell-specific organelle required to repress transposon activity during meiosis. Later seen in the pole plasm at the posterior end of the oocyte as a component of polar granules. Abundantly expressed in the female germline. Gus and faf are required for vas expression in the posterior pole of the oocyte. Expressed both maternally and zygotically. The B30.2/SPRY domain-binding motif mediates recognition by proteins containing a B30.2/SPRY domain. Ubiquitinated during oogenesis. Deubiquitinated by faf, which protects this protein from proteasome-mediated degradation. Defective growth of germline cysts. Fails to efficiently accumulate many localized RNAs, such as Bic-D, orb, osk and nos, but still accumulates grk RNA. Belongs to the DEAD box helicase family. DDX4/VASA subfamily.