J Integr Plant Biol. ›› 2022, Vol. 64 ›› Issue (3): 625-631.DOI: 10.1111/jipb.13209

• Breakthrough Report • Previous Articles     Next Articles

PUB22 and PUB23 U-box E3 ubiquitin ligases negatively regulate 26S proteasome activity under proteotoxic stress conditions

Min Yong Ahn1,2, Dong Hye Seo1,2 and Woo Taek Kim1,2*   

  1. 1 Department of Systems Biology, Division of Life Science, Yonsei University, Seoul 03722, Korea
    2 Institute of Life Science and Biotechnology, Yonsei University, Seoul 03722, Korea

    *Correspondence: Woo Taek Kim (wtkim@yonsei.ac.kr)
  • Received:2021-11-02 Accepted:2021-12-25 Online:2021-12-29 Published:2022-03-01


The mechanism regulating proteasomal activity under proteotoxic stress conditions remains unclear. Here, we showed that arsenite-induced proteotoxic stress resulted in upregulation of Arabidopsis homologous PUB22 and PUB23 U-box E3 ubiquitin ligases and that pub22pub23 double mutants displayed arsenite-insensitive seed germination and root growth phenotypes. PUB22/PUB23 downregulated 26S proteasome activity by promoting the dissociation of the 19S regulatory particle from the holo-proteasome complex, resulting in intracellular accumulation of UbG76V-GFP, an artificial substrate of the proteasome complex, and insoluble poly-ubiquitinated proteins. These results suggest that PUB22/PUB23 play a critical role in arsenite-induced proteotoxic stress response via negative regulation of 26S proteasome integrity.

Editorial Office, Journal of Integrative Plant Biology, Institute of Botany, CAS
No. 20 Nanxincun, Xiangshan, Beijing 100093, China
Tel: +86 10 6283 6133 Fax: +86 10 8259 2636 E-mail: jipb@ibcas.ac.cn
Copyright © 2022 by the Institute of Botany, the Chinese Academy of Sciences
Online ISSN: 1744-7909 Print ISSN: 1672-9072 CN: 11-5067/Q