Abstract
Posttranslational modifications by small ubiquitin-like modifiers (SUMOs) regulate many cellular processes, including genome integrity, gene expression, and ribosome biogenesis. The E2-conjugating enzyme Ubc9 catalyzes the conjugation of SUMOs to epsilon-amino groups of lysine residues in target proteins. Attachment of SUMO moieties to internal lysines in Ubc9 itself can further lead to the formation of polymeric SUMO chains. Mono-and poly-SUMOylations of target proteins provide docking sites for distinct adapter and effector proteins important for regulating discrete SUMO-regulated pathways. However, molecular tools to dissect pathways depending on either mono-or poly-SUMOylation are largely missing. Using a protein-engineering approach, we generated high-affinity SUMO2 variants by phage display that bind the back side binding site of Ubc9 and function as SUMO-based Ubc9 inhibitors (SUBINs). Importantly, we found that distinct SUBINs primarily inhibit poly-SUMO chain formation, whereas mono-SUMOylation was not impaired. Proof-of-principle experiments demonstrated that in a cellular context, SUBINs largely prevent heat shock-triggered polySUMOylation. Moreover, SUBINs abrogated arsenic-induced degradation of promyelocytic leukemia protein. We propose that the availability of the new chain-selective SUMO inhibitors reported here will enable a thorough investigation of poly-SUMO-mediated cellular processes, such as DNA damage responses and cell cycle progression.
| Dokumententyp: | Zeitschriftenartikel | 
|---|---|
| Fakultät: | Biologie > Department Biologie II | 
| Themengebiete: | 500 Naturwissenschaften und Mathematik > 570 Biowissenschaften; Biologie | 
| ISSN: | 0021-9258 | 
| Sprache: | Englisch | 
| Dokumenten ID: | 54687 | 
| Datum der Veröffentlichung auf Open Access LMU: | 14. Jun. 2018 09:57 | 
| Letzte Änderungen: | 23. Dez. 2020 13:26 | 
 
		 
	 
    


