Download MendeleyStructural mechanism for the recognition of E2F1 by the ubiquitin ligase adaptor Cyclin F.
Ngoi, P., Wang, X., Putta, S., Da Luz, R.F., Serrao, V.H.B., Emanuele, M.J., Rubin, S.M.(2025) Proc Natl Acad Sci U S A 122: e2501057122-e2501057122
- PubMed: 40549918
- DOI: https://doi.org/10.1073/pnas.2501057122
- Primary Citation of Related Structures:
9CB3 - PubMed Abstract:
Cyclin F, a noncanonical member of the cyclin protein family, plays a critical role in regulating transitions in the cell division cycle. Unlike canonical cyclins, which bind and activate cyclin-dependent kinases (CDKs), Cyclin F functions as a substrate receptor protein within the Skp1-Cullin-F-box E3 ubiquitin ligase complex, enabling the ubiquitylation of target proteins. The structural features that distinguish Cyclin F as a ligase adaptor and the mechanisms underlying its selective substrate recruitment over Cyclin A, which functions in complex with CDK2 at a similar time in the cell cycle, remain largely unexplored. We utilized single-particle cryoelectron microscopy to elucidate the structure of a Cyclin F-Skp1 complex bound to an E2F1 peptide. The structure and biochemical analysis reveal important differences in the substrate-binding site of Cyclin F compared to Cyclin A. Our findings expand on the canonical cyclin-binding motif (Cy or RxL) and highlight the importance of electrostatics at the E2F1 binding interface, which varies between Cyclin F and Cyclin A. These results advance our understanding of E2F1 regulation and may inform strategies for selectively targeting Cyclin F in cancer or neurodegeneration.
- Department of Chemistry and Biochemistry, University of California, Santa Cruz, CA 95064.
Organizational Affiliation:
