N-ethylmaleimide-sensitive factor (NSF) and valosin-containing protein (p97) are two ATPases known to be involved in transport vesicle/target membrane fusion and fusions between membrane compartments. A trimer of the protein encoded by this gene binds a hexamer of cytosolic p97 and is required for p97-mediated regrowth of Golgi cisternae from mitotic Golgi fragments. Alternative splicing results in multiple transcript variants. A related pseudogene has been identified on chromosome 8.