The N-terminal domain of Rpn4 serves as a portable ubiquitin-independent degron and is recognized by specific 19S RP subunits

► The N-terminal domain of Rpn4 contains a portable ubiquitin-independent degron. ► Ubiquitin-independent degradation of Rpn4 requires the 19S regulatory particle. ► The ubiquitin-independent degron of Rpn4 is recognized by specific 19S subunits.