4JPO:
reference: Reconfiguration of the proteasome during chaperone-mediated assembly., Park S, Li X, Kim HM, Singh CR, Tian G, Hoyt MA, Lovell S, Battaile KP, Zolkiewski M, Coffino P, Roelofs J, Cheng Y, Finley D, Nature. 2013 May 23;497(7450):512-6. doi: 10.1038/nature12123. Epub 2013 May 5. PMID: 23644457

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