Involved in late steps of the endosomal multivesicular bodies (MVB) pathway. Recognizes membrane-associated ESCRT-III assemblies and catalyzes their disassembly, possibly in combination with membrane. ATP + H2O = ADP + H(+) + phosphate Activated by Mg(2+), but not by Ca(2+). Oligomerizes. Membrane-associated in the prevacuolar endosomal compartment. Localizes to the midbody of dividing cells. Expressed highly in head, silk gland and testis with lower levels in fat body and ganglion. Also expressed in ovary and hemolymph, and weakly in Malpighian tube and midgut. Expression is up-regulated during metamorphosis and embryogenesis. Barely expressed in third instar. Expression increases in fourth and fifth instar and is sharply increased in pupa, moth and oosperm. The MIT domain serves as an adapter for ESCRT-III proteins. It forms an asymmetric three-helix bundle that binds amphipathic MIM (MIT interacting motif) helices along the groove between MIT helices 2 and 3 present in a subset of ESCRT-III proteins thus establishing the canonical MIM-MIT interaction. In an extended conformation along the groove between helices 1 and 3, also binds to a type-2 MIT interacting motif (MIM2). Belongs to the AAA ATPase family.