Delivery of chemical cargo to endogenous proteins on live cells.
Ontology highlight
ABSTRACT:
SUBMITTER: Chambers JJ
PROVIDER: S-EPMC3982513 | biostudies-literature | 2014
REPOSITORIES: biostudies-literature
Publications
Delivery of chemical cargo to endogenous proteins on live cells.
Frontiers in chemistry 20140312
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Project description:DNA-protein interactions regulate critical biological processes. Identifying proteins that bind to specific, functional genomic loci is essential for understanding the underlying regulatory mechanisms on a molecular level. Here, we describe a novel co-binding-mediated protein profiling (CMPP) strategy to investigate the interactome of DNA G-quadruplexes (G4s) in cellular chromatin. CMPP involves cell-permeable, functionalized G4-ligand probes that bind endogenous G4s and subsequently crosslink to co-binding G4-interacting proteins in situ. We show the robustness of CMPP on proximity labelling of a G4 binding protein in vitro. Employing this approach in live cells, we identify hundreds of putative G4-interacting proteins from various functional classes. Next, we observe high G4 binding affinity and selectivity for several G4 interactors in vitro and confirm direct G4 interactions for one of the top candidates in chromatin. Our studies provide a chemical approach to map protein interactions of specific nucleic acid features in living cells.
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