. "A multisubunit complex, which caps one or both ends of the proteasome core complex. This complex recognizes and unfolds ubiquitinated proteins, and translocates them to the proteasome core complex." . . . . "proteasome regulatory particle" . "19S regulatory particle" . "modulator complex" . "PA700 proteasome activator" . "PA700-dependent proteasome activator" . . . . . . . .