Rxivist logo

Visualizing ATP-dependent substrate-processing dynamics of the human 26S proteasome at near-atomic resolution

By Yuanchen Dong, Shuwen Zhang, Zhaolong Wu, Xuemei Li, Wei Li Wang, Yanan Zhu, Svetla Stoilova-McPhie, Ying Lu, Daniel Finley, Youdong Mao

Posted 16 Sep 2018
bioRxiv DOI: 10.1101/419051 (published DOI: 10.1038/s41586-018-0736-4)

The proteasome is an ATP-dependent 2.5-megadalton machine responsible for ubiquitylated protein degradation in all eukaryotic cells. Here we present cryo-EM structures of the substrate-engaged human 26S proteasome in seven conformational states at 2.8-3.6 Å resolution, captured during polyubiquitylated protein degradation. These structures visualize a continuum of dynamic substrate-proteasome interactions from ubiquitin recognition to processive substrate translocation, during which ATP hydrolysis sequentially navigate through all six ATPase subunits. Three principle modes of coordinated ATP hydrolysis are observed, featuring hydrolytic events in two oppositely positioned ATPases, in two consecutive ATPases, and in one ATPase at a time. They regulate deubiquitylation, translocation initiation and processive unfolding of substrates, respectively. A collective power stroke in the ATPase motor is generated by synchronized ATP binding and ADP release in the substrate-engaging and disengaging ATPases, respectively. It is amplified largely in the substrate-disengaging ATPase, and propagated unidirectionally by coordinated ATP hydrolysis in the third consecutive ATPase.

Download data

  • Downloaded 673 times
  • Download rankings, all-time:
    • Site-wide: 45,928
    • In biochemistry: 1,160
  • Year to date:
    • Site-wide: 136,480
  • Since beginning of last month:
    • Site-wide: 121,370

Altmetric data

Downloads over time

Distribution of downloads per paper, site-wide