Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.1.26.9 (ribonuclease)
 6,589 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

DNA methylation is one mechanism of epigenetic gene regulation and influences gene expression by recruiting methylcytosine-binding proteins and/or inducing changes in chromatin structure. In mammals, DNA methylation is mediated by at least four DNA methyltransferase (Dnmt) enzymes, including Dnmt1, Dnmt2, Dnmt3a, and Dnmt3b. To understand fully how DNA methylation is involved in gene regulation, knowledge of Dnmt mRNA transcript levels is required, both as a surrogate measure of Dnmt protein levels and also to facilitate an understanding of the regulation of expression of the corresponding genes. Measurement of transcript levels has traditionally been achieved by Northern blot analysis and more recently either by the ribonuclease protection assay or by reverse-transcription polymerase chain reaction (RT-PCR), followed by agarose gel electrophoresis. In the past few years, a form of PCR has been developed that measures the accumulation of PCR product in real time. In conjunction with RT, real-time RT-PCR has become a widely accepted tool for measuring mRNA transcript levels and is now probably the method of choice. This technique is both sensitive and specific and allows for the rapid assessment of Dnmt mRNA transcript levels as well transcripts for other genes that may be involved in DNA methylation.
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PMID:Relative quantitation of DNA methyltransferase mRNA by real-time RT-PCR assay. 1527 19

Dnmt2 proteins are the most conserved members of the DNA methyltransferase enzyme family, but their substrate specificity and biological functions have been a subject of controversy. We show here that, in addition to tRNA(Asp-GTC), tRNA(Val-AAC) and tRNA(Gly-GCC) are also methylated by Dnmt2. Drosophila Dnmt2 mutants showed reduced viability under stress conditions, and Dnmt2 relocalized to stress granules following heat shock. Strikingly, stress-induced cleavage of tRNAs was Dnmt2-dependent, and Dnmt2-mediated methylation protected tRNAs against ribonuclease cleavage. These results uncover a novel biological function of Dnmt2-mediated tRNA methylation, and suggest a role for Dnmt2 enzymes during the biogenesis of tRNA-derived small RNAs.
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PMID:RNA methylation by Dnmt2 protects transfer RNAs against stress-induced cleavage. 2067 93