ATP-dependent chaperone which uses the energy provided by ATP hydrolysis to generate mechanical force to disassemble protein complexes. Plays an essential role in the cytoplasmic maturation steps of pre-60S ribosomal particles by promoting the release of shuttling protein rlp24 from the pre-ribosomal particles. This step facilitates the subsequent release of other shuttling proteins such as nog1 and allows the transition of the pre-ribosomal particles to later maturation forms that bind SPCC550.15c/REI1. ATP + H2O = ADP + H(+) + phosphate Homohexamer; ATP binding induces oligomerization. Forms a ring-shaped particle of about 12 nm diameter, that displays 6-fold radial symmetry. Associates with cytoplasmic pre-60S ribosomal particles. The first ATP-binding region binds ATP with low affinity whereas the second ATP-binding region binds ATP with high affinity. Belongs to the AAA ATPase family. AFG2 subfamily.