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.
|Number of pages||7|
|Journal||Journal of Integrative Plant Biology|
|Publication status||Published - 2022 Mar|
Bibliographical noteFunding Information:
This work was supported by grants from the National Research Foundation (Mid‐Career Researcher Program Project No. 2017R1A2B2006750 and Basic Science Research Program Project No. 2018R1A6A1A03025607), Republic of Korea, to Woo T. Kim.
© 2021 Institute of Botany, Chinese Academy of Sciences
All Science Journal Classification (ASJC) codes
- Biochemistry, Genetics and Molecular Biology(all)
- Plant Science