GSE183465
Evaluation of TET1 non-catalytic functions reveals DNA demethylation independent gene and ERV regulation
Surveillance of DNA methylation is critical for genome stability and epigenetic regulation in mammals. The discovery of the ten-eleven translocation (TET) proteins catalyzing the oxidation from 5-methylcytosine (5mC) to 5-hydroxymethylcytosine (5hmC), 5-formylcytosine (5fC), and 5-carboxylcytosine (5caC) revolutionized the understanding of DNA methylation maintenance and remodeling. Interestingly in recent years evidence accumulated that TET1 also harbours non-catalytic functions. However, the role and mechanism of TET1 DNA demethylation independent functions still remain poorly understood. Here, we use genome engineering, mass spectrometry and quantitative multi-omics approaches to dissect the non-catalytic role of TET1. Strikingly, we find that the majority of transcriptional regulation depends on non-catalytic functions of TET1. Our study identifies TET1 as a scaffold protein and a global regulator of histone modifications. Moreover, we show that the establishment of H3K9me3 and H4K20me3 at ERV1, ERVK and ERVL is mediated by TET1 independent of DNA demethylation. Finally, we provide evidence that repression of endogenous retroviruses depends on the interaction between TET1 and SIN3A. In summary, we found that the non-catalytic functions of TET1 are critical for regulation of gene expression and the silencing of endogenous retroviruses in mESCs. Overall design: ChIP-seq profiling of WT J1, Tet1 KO (clone H9) and Tet1 CM (clone D7) mESC lines.