Mechanistic Insights into Cytosine-N3 Methylation by DNA Methyltransferase DNMT3A

被引：12

作者：

Dukatz, Michael ^{[1
]}

Requena, Cristina E. ^{[2
,3
]}

Emperle, Max ^{[1
]}

Hajkova, Petra ^{[2
,3
]}

Sarkies, Peter ^{[2
,3
]}

Jeltsch, Albert ^{[1
]}

机构：

[1] Univ Stuttgart, Inst Biochem & Tech Biochem, Dept Biochem, Allmandring 31, D-70569 Stuttgart, Germany

[2] MRC London Inst Med Sci, Du Cane Rd, London W12 0NN, England

[3] Imperial Coll London, Inst Clin Sci, Hammersmith Hosp Campus,Du Cane Rd, London W12 0NN, England

来源：

JOURNAL OF MOLECULAR BIOLOGY | 2019年 / 431卷 / 17期

基金：

英国医学研究理事会;

关键词：

DNA methylation; DNA methyltransferase; enzyme mechanism; enzyme catalysis; MOLECULAR ENZYMOLOGY; DYNAMICS;

D O I：

10.1016/j.jmb.2019.06.015

中图分类号：

Q5 [生物化学]; Q7 [分子生物学];

学科分类号：

071010 ; 081704 ;

摘要：

Recently, it has been discovered that different DNA-(cytosine C5)-methyltransferases including DNMT3A generate low levels of 3mC [Rosic et al. (2018), Nat. Genet., 50, 452-459]. This reaction resulted in the co evolution of DNMTs and ALKB2 DNA repair enzymes, but its mechanism remained elusive. Here, we investigated the catalytic mechanism of DNMT3A for cytosine N3 methylation. We generated several DNMT3A variants with mutated catalytic residues and measured their activities in 5mC and 3mC generation by liquid chromatography linked to tandem mass spectrometry. Our data suggest that the methylation of N3 instead of C5 is caused by an inverted binding of the flipped cytosine target base into the active-site pocket of the DNA methyltransferase, which is partially compatible with the arrangement of catalytic amino acid residues. Given that all DNA-(cytosine C5)-methyltransferases have a common catalytic mechanism, it is likely that other enzymes of this class generate 3mC following the same mechanism. (C) 2019 Elsevier Ltd. All rights reserved.

引用

页码：3139 / 3145

页数：7

共 26 条

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