Structural basis for the Rad6 activation by the Bre1 N-terminal domain

  1. Meng Shi
  2. Jiaqi Zhao
  3. Simin Zhang
  4. Wei Huang
  5. Mengfei Li
  6. Xue Bai
  7. Wenxue Zhang
  8. Kai Zhang
  9. Xuefeng Chen  Is a corresponding author
  10. Song Xiang  Is a corresponding author
  1. Tianjin Medical University, China
  2. Wuhan University, China
  3. Tianjin Medical University General Hospital, China

Abstract

The mono-ubiquitination of the histone protein H2B (H2Bub1) is a highly conserved histone post-translational modification that plays critical roles in many fundamental processes. In yeast, this modification is catalyzed by the conserved Bre1-Rad6 complex. Bre1 contains a unique N-terminal Rad6 binding domain (RBD), how it interacts with Rad6 and contributes to the H2Bub1 catalysis is unclear. Here, we present crystal structure of the Bre1 RBD-Rad6 complex and structure-guided functional studies. Our structure provides a detailed picture of the interaction between the dimeric Bre1 RBD and a single Rad6 molecule. We further found that the interaction stimulates Rad6's enzymatic activity by allosterically increasing its active site accessibility and likely contribute to the H2Bub1 catalysis through additional mechanisms. In line with these important functions, we found that the interaction is crucial for multiple H2Bub1-regulated processes. Our study provides molecular insights into the H2Bub1 catalysis.

Data availability

Diffraction data and refined structures of crystal forms 1 and 2 of the KlBre1 RBD-Rad6 complex have been deposited into the protein data bank (www.rcsb.org), with accession codes 7W75 and 7W76, respectively. All data generated or analysed during this study are included in the manuscript and supporting file; source data files are provided for Figures 1-5, figure 1 figure supplement 3 and figure 3 figure supplement 1.

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Author details

  1. Meng Shi

    Department of Biochemistry and Molecular Biology, Tianjin Medical University, Tianjin, China
    Competing interests
    The authors declare that no competing interests exist.
  2. Jiaqi Zhao

    Department of Biochemistry and Molecular Biology, Tianjin Medical University, Tianjin, China
    Competing interests
    The authors declare that no competing interests exist.
  3. Simin Zhang

    College of Life Sciences, Wuhan University, Wuhan, China
    Competing interests
    The authors declare that no competing interests exist.
  4. Wei Huang

    Department of Biochemistry and Molecular Biology, Tianjin Medical University, Tianjin, China
    Competing interests
    The authors declare that no competing interests exist.
  5. Mengfei Li

    College of Life Sciences, Wuhan University, Wuhan, China
    Competing interests
    The authors declare that no competing interests exist.
  6. Xue Bai

    Department of Biochemistry and Molecular Biology, Tianjin Medical University, Tianjin, China
    Competing interests
    The authors declare that no competing interests exist.
  7. Wenxue Zhang

    Department of Radiation Oncology, Tianjin Medical University General Hospital, Tianjin, China
    Competing interests
    The authors declare that no competing interests exist.
  8. Kai Zhang

    Department of Biochemistry and Molecular Biology, Tianjin Medical University, Tianjin, China
    Competing interests
    The authors declare that no competing interests exist.
  9. Xuefeng Chen

    College of Life Sciences, Wuhan University, Wuhan, China
    For correspondence
    xfchen@whu.edu.cn
    Competing interests
    The authors declare that no competing interests exist.
  10. Song Xiang

    Department of Biochemistry and Molecular Biology, Tianjin Medical University, Tianjin, China
    For correspondence
    xiangsong@tmu.edu.cn
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-9314-4684

Funding

National Natural Science Foundation of China (32271259,32071205 and 31870769)

  • Song Xiang

National Natural Science Foundation of China (32070573 and 31872808)

  • Xuefeng Chen

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Copyright

© 2023, Shi et al.

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.

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  1. Meng Shi
  2. Jiaqi Zhao
  3. Simin Zhang
  4. Wei Huang
  5. Mengfei Li
  6. Xue Bai
  7. Wenxue Zhang
  8. Kai Zhang
  9. Xuefeng Chen
  10. Song Xiang
(2023)
Structural basis for the Rad6 activation by the Bre1 N-terminal domain
eLife 12:e84157.
https://doi.org/10.7554/eLife.84157

Share this article

https://doi.org/10.7554/eLife.84157

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