| Autor: |
Samuel R. Witus, Lisa M. Tuttle, Wenjing Li, Alex Zelter, Meiling Wang, Klaiten E. Kermoade, Damien B. Wilburn, Trisha N. Davis, Peter S. Brzovic, Weixing Zhao, Rachel E. Klevit |
| Rok vydání: |
2022 |
| DOI: |
10.1101/2022.08.09.503292 |
| Popis: |
BRCA1/BARD1 is a tumor suppressor E3 ubiquitin (Ub) ligase with roles in DNA damage repair and in transcriptional regulation. BRCA1/BARD1 RING domains interact with nucleosomes to facilitate mono-ubiquitylation of distinct residues on the C-terminal tail of histone H2A. These enzymatic domains constitute a small fraction of the heterodimer, raising the possibility of functional chromatin interactions involving other regions such as the BARD1 C-terminal domains that bind nucleosomes containing the DNA damage signal H2A K15-Ub and H4 K20me0, or portions of the expansive intrinsically disordered regions found in both subunits. Herein, we reveal novel interactions that support robust H2A ubiquitylation activity mediated through a high-affinity, intrinsically disordered DNA-binding region of BARD1. These interactions support BRCA1/BARD1 recruitment to chromatin and sites of DNA damage in cells and contribute to their survival. We also reveal distinct BRCA1/BARD1 complexes that depend on the presence of H2A K15-Ub, including a complex where a single BARD1 subunit spans adjacent nucleosome units. Our findings identify an extensive network of multivalent BARD1- nucleosome interactions that serve as a platform for BRCA1/BARD1-associated functions on chromatin. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
|
