Necessary for the fragmentation of Golgi stacks during mitosis and for their reassembly after mitosis. Involved in the formation of the transitional endoplasmic reticulum (tER). The transfer of membranes from the endoplasmic reticulum to the Golgi apparatus occurs via 50-70 nm transition vesicles which derive from part-rough, part-smooth transitional elements of the endoplasmic reticulum (tER). Vesicle budding from the tER is an ATP-dependent process. Involved in the ubiquitin-proteasome system. Important for oskar mRNA localization and/or anchoring during oogenesis. Involved in germ cell formation. ATP + H2O = ADP + H(+) + phosphate Homohexamer (PubMed:10564274). Interacts with tud, vas, papi and AGO3 (PubMed:18590813, PubMed:21447556). Interacts with Npl4 (PubMed:26471729). Component of the meiotic nuage, also named P granule, a germ-cell-specific organelle required to repress transposon activity during meiosis (PubMed:18590813). Present in the mushroom bodies of the protocerebrum and in the glomeruli of the antennal lobe. Present in nurse cells, oocytes and sperm bundles (at protein level). Present in egg, pupa and imago but not larva (at protein level). Belongs to the AAA ATPase family.