The ubiquitin E3 ligase RNF128 (GRAIL) is regulated by auto-K48-linked ubiquitination, which leads to its proteasomal degradation. RNF128 is bound but not deubiquitinated by OTUB1. USP8 binds the RNF128:OTUB1 complex to remove the ubiquitin attached to GRAIL (Soares et al. 2004, Whiting et al. 2011).
thiol-dependent deubiquitinase activity of USP8:K48polyUb-RNF128:OTUB1 [cytosol]