The PUB (also known as PUG) domain is found in peptide N-glycanase where it functions as a AAA ATPase binding domain [1]. This domain is also found on other proteins linked to the ubiquitin-proteasome system.

1: The PUB domain functions as a p97 binding module in human peptide N-glycanase. Allen MD, Buchberger A, Bycroft M; J Biol Chem. 2006;281:25502-25508. PMID:16807242