A chemical epigenetic tool to probe site-specific DNA-binding protein complexes.

TitleA chemical epigenetic tool to probe site-specific DNA-binding protein complexes.
Publication TypeJournal Article
Year of Publication2025
AuthorsZhu, J, Li, Z, Xue, D, Meng, Z, Shao, S, Pulecio, J, Zhang, G, Huangfu, D, Evans, T, Chen, S, Schultz, PG
JournalProc Natl Acad Sci U S A
Volume122
Issue40
Paginatione2509021122
Date Published2025 Oct 07
ISSN1091-6490
KeywordsBinding Sites, Cell Differentiation, DNA, DNA-Binding Proteins, Epigenesis, Genetic, Humans, Nanog Homeobox Protein, Octamer Transcription Factor-3, Pluripotent Stem Cells, Promoter Regions, Genetic, Protein Binding, SOXB1 Transcription Factors, Transcription Factors
Abstract

Site-specific DNA binding by proteins is critical for regulating transcriptional activity and cell fate decision. However, identifying proteins bound to specific genomic regions (e.g., promoter or enhancer regions) remains challenging. To address this, we developed a chemical epigenetic tool, named Site-specific noncanonical amino acid-mediated capture of protein (SCOPE), incorporating a photo-crosslinking amino acid into a nuclease-deficient dCas9 mutant. Human pluripotent stem cells (hPSCs) carrying SCOPE enable the capture of proteins bound to, in theory, any genomic location, facilitating the study of the cell context-dependent DNA-protein interactions. Using SCOPE, we identified the OCT4/SOX2/CARHSP1 complex binding to the NANOG promoter to maintain pluripotency in hPSCs. During ectoderm differentiation, ZIC2 acts as a competitive inhibitor, binding the same promoter region to downregulate NANOG expression and promote differentiation. Additionally, SCOPE identified that ZNF8 binds to the distal regulatory region of OCT4 to maintain naïve pluripotency. In summary, SCOPE provides a robust system for uncovering cell context-dependent, site-specific genome regulators, offering valuable insights into gene regulation networks driving cell fate transitions.

DOI10.1073/pnas.2509021122
Alternate JournalProc Natl Acad Sci U S A
PubMed ID41037631
Grant ListR01DK137517 / / HHS | NIH | National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) /
R01DK124463 / / HHS | NIH | National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) /
1R01DK130454 / / HHS | NIH | National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) /