A New DUB Makes Linear Ubiquitin a Party to Its Own Destruction

Linear ubiquitin (Ub) plays a role in nuclear factor κB signaling, but the deubiquitinating enzyme that disassembles these chains was unknown. In this issue of Cell, Keusekotten et al. identify a new enzyme that disassembles linear chains with the use of a mechanism that relies on Ub itself to help catalyze peptide bond cleavage.