Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:2.1.1.37 (DNA methyltransferase)
 4,983 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The eukaryotic DNA cytosine-5-methyltransferase (E.C.2.1.1.37) is known to methylate cytosine in DNA mainly, but not exclusively in C-G. In the present study the minor, non-C-G recognition sequences of a rat DNA methyltransferase were analyzed by Maxam-Gilbert sequencing of in vitro methylated SV40 DNA. The enzyme methylates C-A and C-T at a 50-fold lower initial rate than C-G. Methylation of C-C at the 5'C was not observed in the piece of DNA sequenced. The methylation of C-A is very low in the trinucleotides ACA and CAC, the other C-A containing trinucleotides in DNA are much better methylacceptors. C-T was found methylated predominantly in the sequences CCTAA, ACTAA, and ACTGT. A comparison of the activity with different substrates is in favour of the enzyme making its recognition in the major groove of the DNA.
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PMID:Non-C-G recognition sequences of DNA cytosine-5-methyltransferase from rat liver. 254 90

Eco72I from Escherichia coli RFL72 is a type-II restriction-modification (R-M) system recognizing and cleaving the sequence 5'-CAC decreases GTG-3'. The R-M genes are transcribed divergently and between the two genes is a small open reading frame codirectional to the R gene. This small ORF acts both to stimulate ENase expression and to depress DNA methyltransferase synthesis. The activity of beta Gal produced from the eco72IM::lacZ translational fusion increased tenfold, and eco72IR::lacZ translational fusion beta Gal activity decreased 130-fold when eco72IC was inactivated by a frameshift mutation. Analysis of nucleotide sequences of R-M systems, containing C genes, revealed a 5'-ACCTTATAGTC-3' consensus sequence upstream from the regulatory genes in all six analysed R-M systems. This sequence, named C-box, may play the role of an operator sequence.
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PMID:The eco72IC gene specifies a trans-acting factor which influences expression of both DNA methyltransferase and endonuclease from the Eco72I restriction-modification system. 760 93

In vertebrates, DNA methylation predominantly occurs at CG dinucleotides however, widespread non-CG methylation (mCH) has been reported in mammalian embryonic stem cells and in the brain. In mammals, mCH is found at CAC trinucleotides in the nervous system, where it is associated with transcriptional repression, and at CAG trinucleotides in embryonic stem cells, where it positively correlates with transcription. Moreover, CAC methylation appears to be a conserved feature of adult vertebrate brains. Unlike any of those methylation signatures, here we describe a novel form of mCH that occurs in the TGCT context within zebrafish mosaic satellite repeats. TGCT methylation is inherited from both male and female gametes, remodelled during mid-blastula transition, and re-established during gastrulation in all embryonic layers. Moreover, we identify DNA methyltransferase 3ba (Dnmt3ba) as the primary enzyme responsible for the deposition of this mCH mark. Finally, we observe that TGCT-methylated repeats are specifically associated with H3K9me3-marked heterochromatin suggestive of a functional interplay between these two gene-regulatory marks. Altogether, this work provides insight into a novel form of vertebrate mCH and highlights the substrate diversity of vertebrate DNA methyltransferases.
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PMID:Developmental remodelling of non-CG methylation at satellite DNA repeats. 3327 98