Fiche publication
Date publication
septembre 2025
Journal
Nucleic acids research
Auteurs
Membres identifiés du Cancéropôle Est :
Dr BOURDERIOUX Aurélie
,
Mr HUMBERT Nicolas
,
Dr MOUSLI Marc
,
Dr BOMBARDA Elisa
,
Dr DZIUBA Dmytro
Tous les auteurs :
Mukherjee D, Ciaco S, Martinez-Fernandez L, Gavvala K, Bombarda E, Bourdérioux A, Dziuba D, Hanser F, Humbert N, Javed A, Mousli M, Singh P, Tor Y, Improta R, Mori M, Mély Y
Lien Pubmed
Résumé
Ubiquitin-like, containing PHD and RING fingers domains 1 (UHRF1) plays a pivotal role in replicating DNA methylation patterns during cell division. Acting as a DNA reader, UHRF1, via its SET- and RING-associated (SRA) domain, recognizes hemi-methylated (HM) CpG sites and flips 5-methylcytosine (5mC) nucleobases. This flipping triggers DNA methyltransferase 1 (DNMT1) recruitment to methylate cytosine in the complementary strand. To investigate the SRA-induced base-flipping mechanism, we introduced thienoguanosine (thG), a fluorescent guanosine analogue, at four positions in HM and non-methylated duplexes. The interactions of these labelled duplexes with wild-type SRA and a G448D mutant (incapable of base-flipping) were monitored using a combination of stopped-flow fluorescence measurements, molecular dynamics simulations, and quantum mechanical calculations. We show that 5mC and C residues are flipped with similar rate constants. However, while C residues rapidly revert to their original state, enabling SRA to continue reading or dissociate, SRA complexes with flipped 5mC undergo a slow conformational rearrangement, leading to the final conformation crucial for DNMT1 recruitment. Taken together, our findings suggest that base flipping is used to discriminate 5mC from C residues, while the ensuing conformational rearrangement drives DNMT1 recruitment.
Mots clés
Ubiquitin-Protein Ligases, chemistry, CCAAT-Enhancer-Binding Proteins, chemistry, DNA Methylation, Humans, DNA (Cytosine-5-)-Methyltransferase 1, metabolism, 5-Methylcytosine, metabolism, Molecular Dynamics Simulation, Protein Domains, Epigenesis, Genetic, CpG Islands, DNA, chemistry, Protein Binding
Référence
Nucleic Acids Res. 2025 09 5;53(17):
