Download MendeleyStructural basis for the recognition and ubiquitylation of type-2 N-degron substrate by PRT1 plant N-recognin.
Yang, W.S., Kim, S.H., Kim, M., Shin, H., Lee, J., Sandmann, A., Park, O.K., Dissmeyer, N., Song, H.K.(2025) Nat Commun 16: 7817-7817
- PubMed: 40841552
- DOI: https://doi.org/10.1038/s41467-025-63282-9
- Primary Citation of Related Structures:
8ZG8, 8ZG9, 8ZGA, 8ZGB - PubMed Abstract:
PROTEOLYSIS1 (PRT1), an N-recognin of Arabidopsis thaliana, recognizes the N-terminal aromatic hydrophobic residue (Tyr/Phe/Trp) of its substrates and ubiquitylates them for degradation by the ubiquitin-proteasome system. Herein, we report the structures of the ZZ domain of PRT1 (PRT1 ZZ ) in complex with bulky hydrophobic N-degron peptides. Unlike other ZZ domains, PRT1 ZZ has an unusual binding site with two hydrophobic regions. The N-terminal aromatic residues of N-degrons interact with Ile333 and Phe352 in the flexible loops, which undergo a conformational change. Notably, we identify a third residue from the N-terminus of the substrate that participates in the hydrophobic network with PRT1 ZZ . Moreover, AlphaFold prediction and biochemical assays revealed that the tandem RING1 and RING2 domains of PRT1 interact intramolecularly. The dimeric RING domains in a single protein represent a unique feature among the RING-type E3 ligases. The biochemical assays using the N-terminal tyrosine-exposed substrate, BIG BROTHER, show that the intramolecular RING dimer is essential for PRT1's robust activity. Therefore, this study expands our knowledge of the structural repertoire in the N-degron pathway and provides insights into the regulation of E3 ligases containing tandem RING domains.
- Department of Life Sciences, Korea University, Seongbuk-gu, Seoul, South Korea.
Organizational Affiliation:
