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Chemical Inactivation of the E3 Ubiquitin Ligase Cereblon by Pomalidomide-based Homo-PROTACs
Published on: May 15, 2019
Ratjadone and leptomycin B block CRM1-dependent nuclear export by identical mechanisms
Torsten Meissner1, Eberhard Krause, Uwe Vinkemeier
1Abteilung Zelluläre Signalverarbeitung, Leibniz-Forschungsinstitut für Molekulare Pharmakologie, Freie Universität Berlin, Robert-Rössle-Str. 10, 13125 Berlin, Germany.
Abstract:
Research on the export of proteins and nucleic acids from the nucleus to the cytoplasm has greatly gained from the discovery that the actinobacterial toxin leptomycin B (LMB) specifically inactivates the export receptor chromosomal region maintenance 1 (CRM1). Recently, it was shown that myxobacterial cytotoxins, named ratjadones (RATs), also bind to CRM1 and inhibit nuclear export. However, the reaction mechanism of RATs was not resolved. Here, we show that LMB and RAT A employ the same molecular mechanism to inactivate CRM1. Alkylation of residue Cys528 of CRM1 determines both LMB and RAT sensitivity and prevents nuclear export of CRM1 cargo proteins.
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