Genome-wide mapping of the TET3 CXXC domain binding sites

The TET3 CXXC domain has unique DNA binding properties. It binds to DNA in a cytosine-dependent manner that prefers binding to CpG dinucleotides but is not restricted by the CpG-content, distinct from other well-characterized CXXC domains. To map the TET3 CXXC domain binding sites across the human genome, we purified the GST-tagged TET3 CXXC domain protein and performed the GST pull-down assay using the genomic DNA purified from HEK293T cells. The enriched DNA fragments were then sequenced and aligned to human genome(hg19). We used the GST pull-down assay followed by DNA deep sequencing to map the DNA bound by the TET3 CXXC domain in vitro.