EPFL BioE Talks SERIES "Structural and Molecular Basis of Nucleosome Formation and Its Regulation"
Event details
| Date | 31.03.2025 |
| Hour | 12:15 › 13:15 |
| Speaker | Prof. Ji-Joon Song, Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), Daejeon (KOR) |
| Location | Online |
| Category | Conferences - Seminars |
| Event Language | English |
WEEKLY EPFL BIOE TALKS SERIES (sandwiches provided)
Abstract:
Nucleosome assembly is essential for chromatin organization and gene regulation, requiring histone chaperones. Here, we reveal the structural and molecular mechanisms of nucleosome formation and its regulation. We show that the ATAD2 homolog Abo1 facilitates ATP-dependent histone H3-H4 loading onto DNA, as demonstrated by integrated biophysical approach using cryo-EM and single-molecule DNA curtain assay. Our further structural analysis reveals key conformational changes that enable histone deposition, with high-speed atomic force microscopy (HS-AFM) visualizing Abo1’s dynamic transitions. In contrast, nucleosome assembly is negatively regulated by CODANIN-1, which inhibits the histone chaperone ASF1. Our cryo-EM structure of the CODANIN-1_ASF1A complex reveals that CODANIN-1 sequesters ASF1 via B-domains and histone mimic helices, preventing H3-H4 complex formation and restricting ASF1 in the cytoplasm. These findings provide structural insights into the mechanisms of histone deposition and its regulation, shedding light on the balance between nucleosome formation and inhibition.
Bio:
Ji-Joon Song is a Professor in the Department of Biological Sciences at KAIST (Korea Advanced Institute of Science and Technology). He received his. B.S. at Seoul National University, and his Ph.D. in structural biology at the Cold Spring Harbor Laboratory. During his Ph.D., he determined the first structure of Argonaute and identified the Slicer in RNAi. He then joined Bob Kingston's group as a research fellow to investigate epigenetic mechanism of gene regulation at Massachusetts General Hospital, Harvard Medical School. The research in Song Lab at KAIST focuses on understanding the molecular mechanisms of epigenetic gene regulation and neurodegenerative disease using integrative structural approaches.
Zoom link (with one-time registration for the whole series) for attending remotely: https://go.epfl.ch/EPFLBioETalks
Instructions for 1st-year Ph.D. students who are under EDBB’s mandatory seminar attendance rule:
IN CASE you cannot attend in-person in the room, please make sure to
Abstract:
Nucleosome assembly is essential for chromatin organization and gene regulation, requiring histone chaperones. Here, we reveal the structural and molecular mechanisms of nucleosome formation and its regulation. We show that the ATAD2 homolog Abo1 facilitates ATP-dependent histone H3-H4 loading onto DNA, as demonstrated by integrated biophysical approach using cryo-EM and single-molecule DNA curtain assay. Our further structural analysis reveals key conformational changes that enable histone deposition, with high-speed atomic force microscopy (HS-AFM) visualizing Abo1’s dynamic transitions. In contrast, nucleosome assembly is negatively regulated by CODANIN-1, which inhibits the histone chaperone ASF1. Our cryo-EM structure of the CODANIN-1_ASF1A complex reveals that CODANIN-1 sequesters ASF1 via B-domains and histone mimic helices, preventing H3-H4 complex formation and restricting ASF1 in the cytoplasm. These findings provide structural insights into the mechanisms of histone deposition and its regulation, shedding light on the balance between nucleosome formation and inhibition.
Bio:
Ji-Joon Song is a Professor in the Department of Biological Sciences at KAIST (Korea Advanced Institute of Science and Technology). He received his. B.S. at Seoul National University, and his Ph.D. in structural biology at the Cold Spring Harbor Laboratory. During his Ph.D., he determined the first structure of Argonaute and identified the Slicer in RNAi. He then joined Bob Kingston's group as a research fellow to investigate epigenetic mechanism of gene regulation at Massachusetts General Hospital, Harvard Medical School. The research in Song Lab at KAIST focuses on understanding the molecular mechanisms of epigenetic gene regulation and neurodegenerative disease using integrative structural approaches.
Zoom link (with one-time registration for the whole series) for attending remotely: https://go.epfl.ch/EPFLBioETalks
Instructions for 1st-year Ph.D. students who are under EDBB’s mandatory seminar attendance rule:
IN CASE you cannot attend in-person in the room, please make sure to
- send D. Reinhard a note well ahead of time (ideally before seminar day), informing that you plan to attend the talk online, and, during seminar:
- be signed in on Zoom with a recognizable user name (not any alias making it difficult or impossible to identify you).
Practical information
- Informed public
- Registration required
Organizer
- Prof. Matteo Dal Peraro, Institute of Bioengineering
Contact
- Institute of Bioengineering (IBI), Dietrich REINHARD