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bioRxiv · 10.1101/2024.11.08.622741

Structure of the TXNL1-bound proteasome

Gao, J.·Nardone, C.·Yip, M. C.·Chino, H.·Gu, X.·Mirman, Z.·Rale, M. J.·Paulo, J. A.·Elledge, S. J.·Shao, S.
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Abstract

Proteasomes degrade diverse proteins in different cellular contexts through incompletely defined regulatory mechanisms. Here, we report the cryo-EM structure of thioredoxin-like protein 1 (TXNL1) bound to the 19S regulatory particle of proteasomes via interactions with PSMD1/Rpn2, PSMD4/Rpn10, and PSMD14/Rpn11. These interactions are necessary for the ubiquitin-independent degradation of TXNL1 upon cellular exposure to metal- or metalloid-containing oxidative agents, thereby establishing a structural basis for the stress-induced degradation of TXNL1.

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Gao, J., Nardone, C., Yip, M. C., Chino, H., Gu, X., Mirman, Z., Rale, M. J., Paulo, J. A., Elledge, S. J., Shao, S.. 2024-11-10. Structure of the TXNL1-bound proteasome. https://doi.org/10.1101/2024.11.08.622741

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