Infotmation
MG-132 is a potent, cell permeable and ive proteasome inhibitor (Ki = 4nM).1 It inhibits NF-κB activation by preventing IκB degradation (IC₅₀ = 3μM). The peptide blocks degradation of short-lived proteins, which in turn induces HSP and ER chaperone expression, leading to thermotolerance (1μM MG-132, 2 h.). It also stimulates neurite outgrowth in PC12 cells (20nM optimal). The peptide has also been reported to increase the survival rate of mesenchymal stem cells following their transplantation. IC₅₀’s for inhibition of Suc-LLVY-AMC and Z-LLL-AMC cleaving activities of proteasome were 0.85 and 0.1μM respectively. The ubiquitin-proteasome system (UPS) and autophagy serve as two complementary, reciprocally regulated protein degradation systems, thus blockade of UPS by MG-132 activates autophagy.