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Updated: Jul 12, 2025
09:40
In Vivo Detection and Analysis of Rb Protein SUMOylation in Human Cells
Published on: November 2, 2017
7.3K
The G1/S transition is promoted by Rb degradation via the E3 ligase UBR5
Shuyuan Zhang1, Lucas Fuentes Valenzuela1, Evgeny Zatulovskiy1
1Department of Biology, Stanford University, Stanford, CA 94305.
Biorxiv : the Preprint Server for Biology
|October 24, 2023
Summary
The retinoblastoma protein (Rb) concentration drop during cell division is controlled by phosphorylation-dependent protein degradation. UBR5 targets Rb for degradation, impacting cell cycle progression and cancer therapy efficacy.
Area of Science:
- Cell Biology
- Molecular Biology
- Cancer Research
Background:
- The retinoblastoma protein (Rb) is a key regulator of the G1/S cell cycle transition and a tumor suppressor.
- Rb activity is modulated by Cyclin D-Cdk4/6 kinase complexes and also by changes in its concentration during the cell cycle.
- The mechanisms controlling Rb concentration changes in G1 remain largely unknown.
Conclusions:
- UBR5-mediated degradation is a critical mechanism controlling Rb levels and cell cycle progression.
- Targeting UBR5 offers a potential strategy to enhance the efficacy of Cdk4/6 inhibitor cancer therapies.
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