4e9e: Difference between revisions
No edit summary |
No edit summary |
||
| Line 1: | Line 1: | ||
[[ | ==Structure of the glycosylase domain of MBD4== | ||
<StructureSection load='4e9e' size='340' side='right' caption='[[4e9e]], [[Resolution|resolution]] 1.90Å' scene=''> | |||
== Structural highlights == | |||
<table><tr><td colspan='2'>[[4e9e]] is a 1 chain structure with sequence from [http://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4E9E OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=4E9E FirstGlance]. <br> | |||
</td></tr><tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[3iho|3iho]], [[4e9f|4e9f]], [[4e9g|4e9g]], [[4e9h|4e9h]], [[4ea4|4ea4]], [[4eab|4eab]]</td></tr> | |||
<tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">MBD4, MED1 ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=9606 Homo sapiens])</td></tr> | |||
<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=4e9e FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4e9e OCA], [http://www.rcsb.org/pdb/explore.do?structureId=4e9e RCSB], [http://www.ebi.ac.uk/pdbsum/4e9e PDBsum]</span></td></tr> | |||
</table> | |||
<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®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |||
</div> | |||
==See Also== | |||
*[[Methyl CpG binding protein|Methyl CpG binding protein]] | |||
== | == References == | ||
[[ | <references/> | ||
__TOC__ | |||
== | </StructureSection> | ||
< | |||
[[Category: Homo sapiens]] | [[Category: Homo sapiens]] | ||
[[Category: Morera, S | [[Category: Morera, S]] | ||
[[Category: Vigouroux, A | [[Category: Vigouroux, A]] | ||
[[Category: Hhh dna glycosylase superfamily]] | [[Category: Hhh dna glycosylase superfamily]] | ||
[[Category: Hydrolase]] | [[Category: Hydrolase]] | ||
Revision as of 20:07, 9 December 2014
Structure of the glycosylase domain of MBD4Structure of the glycosylase domain of MBD4
Structural highlights
Publication Abstract from PubMedActive 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[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
|
| ||||||||||||||||||