Enables microtubule binding activity and polyubiquitin modification-dependent protein binding activity. Involved in several processes, including mitotic spindle assembly; protein K63-linked deubiquitination; and response to ischemia. Located in cytoplasm. Part of BRISC complex. Colocalizes with microtubule minus-end; midbody; and spindle pole centrosome. [provided by Alliance of Genome Resources, Apr 2022]