4z3c
From Proteopedia
Zinc finger region of human TET3 in complex with CpG DNA
Structural highlights
DiseaseTET3_HUMAN Non-specific syndromic intellectual disability. The disease is caused by variants affecting the gene represented in this entry. FunctionTET3_HUMAN Dioxygenase that catalyzes the conversion of the modified genomic base 5-methylcytosine (5mC) into 5-hydroxymethylcytosine (5hmC) and plays a key role in epigenetic chromatin reprogramming in the zygote following fertilization (PubMed:31928709). Also mediates subsequent conversion of 5hmC into 5-formylcytosine (5fC), and conversion of 5fC to 5-carboxylcytosine (5caC). Conversion of 5mC into 5hmC, 5fC and 5caC probably constitutes the first step in cytosine demethylation (By similarity). Selectively binds to the promoter region of target genes and contributes to regulate the expression of numerous developmental genes (PubMed:23217707). In zygotes, DNA demethylation occurs selectively in the paternal pronucleus before the first cell division, while the adjacent maternal pronucleus and certain paternally-imprinted loci are protected from this process. Participates in DNA demethylation in the paternal pronucleus by mediating conversion of 5mC into 5hmC, 5fC and 5caC. Does not mediate DNA demethylation of maternal pronucleus because of the presence of DPPA3/PGC7 on maternal chromatin that prevents TET3-binding to chromatin (By similarity). In addition to its role in DNA demethylation, also involved in the recruitment of the O-GlcNAc transferase OGT to CpG-rich transcription start sites of active genes, thereby promoting histone H2B GlcNAcylation by OGT (PubMed:23353889). Binds preferentially to DNA containing cytidine-phosphate-guanosine (CpG) dinucleotides over CpH (H=A, T, and C), hemimethylated-CpG and hemimethylated-hydroxymethyl-CpG (PubMed:29276034).[UniProtKB:Q8BG87][1] [2] [3] [4] Publication Abstract from PubMedThe CXXC domain, first identified as the reader of unmodified CpG dinucleotide, plays important roles in epigenetic regulation by targeting various activities to CpG islands. Here we systematically measured and compared the DNA-binding selectivities of all known human CXXC domains by different binding assays, and complemented the existing function-based classification of human CXXC domains with a classification based on their DNA selectivities. Through a series of crystal structures of CXXC domains with DNA ligands, we unravel the molecular mechanisms of how these CXXC domains, including single CXXC domains and tandem CXXC-PHD domains, recognize distinct DNA ligands, which further supports our classification of human CXXC domains and also provides insights into selective recruitment of chromatin modifiers to their respective targets via CXXC domains recognizing different genomic DNA sequences. Our study facilitates the understanding of the relationship between the DNA-binding specificities of the CXXC proteins and their biological functions. DNA Sequence Recognition of Human CXXC Domains and Their Structural Determinants.,Xu C, Liu K, Lei M, Yang A, Li Y, Hughes TR, Min J Structure. 2017 Dec 16. pii: S0969-2126(17)30396-9. doi:, 10.1016/j.str.2017.11.022. PMID:29276034[5] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
|
Categories: Homo sapiens | Large Structures | Synthetic construct | Arrowsmith CH | Bountra C | Dong A | Edwards AM | Liu K | Min J | Tempel W | Xu C