Enables K48-linked polyubiquitin modification-dependent protein binding activity and identical protein binding activity. Involved in DNA damage response; negative regulation of double-strand break repair via homologous recombination; and regulation of catabolic process. Located in several cellular c
omponents, including autophagosome; proteasome complex; and site of DNA damage. Part of protein-containing complex. [provided by Alliance of Genome Resources, Apr 2025]