Ubiquitin-Proteasome System

Intracellular pathway in which proteins are covalently tagged with one or more ubiquitin molecules through an E1–E2–E3 enzymatic cascade and, when marked by degradation-associated ubiquitin signals, are recognized, unfolded and proteolytically degraded by the 26S proteasome; this system controls selective protein turnover and modulates signaling by removing specific soluble or short-lived proteins