4e9f: Difference between revisions

No edit summary
No edit summary
 
Line 4: Line 4:
== Structural highlights ==
== Structural highlights ==
<table><tr><td colspan='2'>[[4e9f]] is a 3 chain structure with sequence from [https://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4E9F OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=4E9F FirstGlance]. <br>
<table><tr><td colspan='2'>[[4e9f]] is a 3 chain structure with sequence from [https://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4E9F OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=4E9F FirstGlance]. <br>
</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=3DR:1,2-DIDEOXYRIBOFURANOSE-5-PHOSPHATE'>3DR</scene>, <scene name='pdbligand=EDO:1,2-ETHANEDIOL'>EDO</scene></td></tr>
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 1.79&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=3DR:1,2-DIDEOXYRIBOFURANOSE-5-PHOSPHATE'>3DR</scene>, <scene name='pdbligand=EDO:1,2-ETHANEDIOL'>EDO</scene></td></tr>
<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=4e9f FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4e9f OCA], [https://pdbe.org/4e9f PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=4e9f RCSB], [https://www.ebi.ac.uk/pdbsum/4e9f PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=4e9f ProSAT]</span></td></tr>
<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=4e9f FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4e9f OCA], [https://pdbe.org/4e9f PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=4e9f RCSB], [https://www.ebi.ac.uk/pdbsum/4e9f PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=4e9f ProSAT]</span></td></tr>
</table>
</table>
== Function ==
== Function ==
[[https://www.uniprot.org/uniprot/MBD4_HUMAN MBD4_HUMAN]] Mismatch-specific DNA N-glycosylase involved in DNA repair. Has thymine glycosylase activity and is specific for G:T mismatches within methylated and unmethylated CpG sites. Can also remove uracil or 5-fluorouracil in G:U mismatches. Has no lyase activity. Was first identified as methyl-CpG-binding protein.<ref>PMID:10097147</ref> <ref>PMID:10930409</ref>
[https://www.uniprot.org/uniprot/MBD4_HUMAN MBD4_HUMAN] Mismatch-specific DNA N-glycosylase involved in DNA repair. Has thymine glycosylase activity and is specific for G:T mismatches within methylated and unmethylated CpG sites. Can also remove uracil or 5-fluorouracil in G:U mismatches. Has no lyase activity. Was first identified as methyl-CpG-binding protein.<ref>PMID:10097147</ref> <ref>PMID:10930409</ref>  
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Active DNA demethylation in mammals occurs via hydroxylation of 5-methylcytosine to 5-hydroxymethylcytosine (5hmC) by the ten-eleven translocation family of proteins (TETs). 5hmC residues in DNA can be further oxidized by TETs to 5-carboxylcytosines and/or deaminated by the Activation Induced Deaminase/Apolipoprotein B mRNA-editing enzyme complex family proteins to 5-hydromethyluracil (5hmU). Excision and replacement of these intermediates is initiated by DNA glycosylases such as thymine-DNA glycosylase (TDG), methyl-binding domain protein 4 (MBD4) and single-strand specific monofunctional uracil-DNA glycosylase 1 in the base excision repair pathway. Here, we report detailed biochemical and structural characterization of human MBD4 which contains mismatch-specific TDG activity. Full-length as well as catalytic domain (residues 426-580) of human MBD4 (MBD4(cat)) can remove 5hmU when opposite to G with good efficiency. Here, we also report six crystal structures of human MBD4(cat): an unliganded form and five binary complexes with duplex DNA containing a T*G, 5hmU*G or AP*G (apurinic/apyrimidinic) mismatch at the target base pair. These structures reveal that MBD4(cat) uses a base flipping mechanism to specifically recognize thymine and 5hmU. The recognition mechanism of flipped-out 5hmU bases in MBD4(cat) active site supports the potential role of MBD4, together with TDG, in maintenance of genome stability and active DNA demethylation in mammals.
 
Biochemical and structural characterization of the glycosylase domain of MBD4 bound to thymine and 5-hydroxymethyuracil-containing DNA.,Morera S, Grin I, Vigouroux A, Couve S, Henriot V, Saparbaev M, Ishchenko AA Nucleic Acids Res. 2012 Jul 30. PMID:22848106<ref>PMID:22848106</ref>
 
From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 4e9f" style="background-color:#fffaf0;"></div>


==See Also==
==See Also==

Proteopedia Page Contributors and Editors (what is this?)Proteopedia Page Contributors and Editors (what is this?)

OCA