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Cancer Biology & Therapy Dec 2023RNA methyltransferase nucleolar protein p120 (NOP2), commonly referred to as NOP2/Sun RNA methyltransferase family member 1 (NSUN1), is involved in cell proliferation...
RNA methyltransferase nucleolar protein p120 (NOP2), commonly referred to as NOP2/Sun RNA methyltransferase family member 1 (NSUN1), is involved in cell proliferation and is highly expressed in various cancers. However, its role in high-grade serous ovarian cancer (HGSOC) remains unclear. Our study investigated the expression of NOP2 in HGSOC tissues and normal fimbria tissues, and found that NOP2 was significantly upregulated in HGSOC tissues. Our experiments showed that NOP2 overexpression promoted cell proliferation and and increased the migration and invasion ability of HGSOC cells . Furthermore, we identified Rap guanine nucleotide exchange factor 4 (RAPGEF4) as a potential downstream target of NOP2 in HGSOC. Finally, our findings suggest that the regulation of NOP2 and RAPGEF4 may depend on mC methylation levels.
Topics: Humans; Female; RNA; Methyltransferases; Ovarian Neoplasms; Cell Proliferation; Nuclear Proteins; Guanine Nucleotide Exchange Factors; tRNA Methyltransferases
PubMed: 37800580
DOI: 10.1080/15384047.2023.2263921 -
Journal of Cardiovascular Translational... Jun 2023Epitranscriptomics is the emerging field of research that comprises the study of epigenetics changes in RNAs. Progressing development in the field of epigenetics has... (Review)
Review
Epitranscriptomics is the emerging field of research that comprises the study of epigenetics changes in RNAs. Progressing development in the field of epigenetics has helped to manage and comprehend human diseases. RNA methylation regulates all aspects of RNA functions, which are involved in the pathogenesis of human diseases. Interestingly, RNA m5C methylation is significantly linked to various types of human disease, including cardiovascular diseases (CVD). The m5C methylation is controlled by m5C regulatory proteins, which act as methyltransferase, demethyltransferase, and RNA-binding protein. Dysregulated expression in m5C regulatory proteins is significantly associated with cardiovascular disease, and these regulatory proteins have crucial roles in biological and cellular functions. This review is mainly focused on the role of RNA m5C modification in CVD and mitochondrial dysfunction. Thus, m5C will contribute to discovering the new diagnostic marker and therapeutic target for CVD.
Topics: Humans; Cardiovascular Diseases; RNA; Methyltransferases; Epigenesis, Genetic
PubMed: 36318418
DOI: 10.1007/s12265-022-10336-8 -
ACS Chemical Biology Jan 2015Growing evidence suggests that histone methyltransferases (HMTs, also known as protein methyltransferases (PMTs)) play an important role in diverse biological processes... (Review)
Review
Growing evidence suggests that histone methyltransferases (HMTs, also known as protein methyltransferases (PMTs)) play an important role in diverse biological processes and human diseases by regulating gene expression and the chromatin state. Therefore, HMTs have been increasingly recognized by the biomedical community as a class of potential therapeutic targets. High quality chemical probes of HMTs, as tools for deciphering their physiological functions and roles in human diseases and testing therapeutic hypotheses, are critical for advancing this promising field. In this review, we focus on the discovery, characterization, and biological applications of chemical probes for HMTs.
Topics: Animals; Drug Design; Histone Methyltransferases; Histone-Lysine N-Methyltransferase; Humans; Lysine; Models, Molecular; Protein Binding; Protein Processing, Post-Translational; Small Molecule Libraries; Structure-Activity Relationship
PubMed: 25423077
DOI: 10.1021/cb500785t -
Development (Cambridge, England) May 2023Histone modifications regulate chromatin remodeling and gene expression in development and diseases. DOT1L, the sole histone H3K79 methyltransferase, is essential for...
Histone modifications regulate chromatin remodeling and gene expression in development and diseases. DOT1L, the sole histone H3K79 methyltransferase, is essential for embryonic development. Here, we report that DOT1L regulates male fertility in mouse. DOT1L associates with MLLT10 in testis. DOT1L and MLLT10 localize to the sex chromatin in meiotic and post-meiotic germ cells in an inter-dependent manner. Loss of either DOT1L or MLLT10 leads to reduced testis weight, decreased sperm count and male subfertility. H3K79me2 is abundant in elongating spermatids, which undergo the dramatic histone-to-protamine transition. Both DOT1L and MLLT10 are essential for H3K79me2 modification in germ cells. Strikingly, histones are substantially retained in epididymal sperm from either DOT1L- or MLLT10-deficient mice. These results demonstrate that H3K79 methylation promotes histone replacement during spermiogenesis.
Topics: Animals; Male; Mice; Fertility; Histone Methyltransferases; Histone-Lysine N-Methyltransferase; Histones; Methylation; Methyltransferases; Semen; Spermatogenesis; Transcription Factors
PubMed: 37082953
DOI: 10.1242/dev.201501 -
Angewandte Chemie (International Ed. in... Nov 2022Methods for regioselective N-methylation and -alkylation of unsaturated heterocycles with "off the shelf" reagents are highly sought-after. This reaction could...
Methods for regioselective N-methylation and -alkylation of unsaturated heterocycles with "off the shelf" reagents are highly sought-after. This reaction could drastically simplify synthesis of privileged bioactive molecules. Here we report engineered and natural methyltransferases for challenging N-(m)ethylation of heterocycles, including benzimidazoles, benzotriazoles, imidazoles and indazoles. The reactions are performed through a cyclic enzyme cascade that consists of two methyltransferases using only iodoalkanes or methyl tosylate as simple reagents. This method enables the selective synthesis of important molecules that are otherwise difficult to access, proceeds with high regioselectivity (r.r. up to >99 %), yield (up to 99 %), on a preparative scale, and with nearly equimolar concentrations of simple starting materials.
Topics: Methylation; Biocatalysis; Methyltransferases; Alkylation; Imidazoles
PubMed: 36202763
DOI: 10.1002/anie.202213056 -
Advances in Experimental Medicine and... 2022DNA methyltransferases (MTases) uniquely combine the ability to recognize and covalently modify specific target sequences in DNA using the ubiquitous cofactor...
DNA methyltransferases (MTases) uniquely combine the ability to recognize and covalently modify specific target sequences in DNA using the ubiquitous cofactor S-Adenosyl-L-methionine (AdoMet). Although DNA methylation plays important roles in biological signaling, the transferred methyl group is a poor reporter and is highly inert to further biocompatible derivatization. To unlock the biotechnological power of these enzymes, extended cofactor AdoMet analogs have been developed that enable targeted MTase-directed attachment of larger moieties containing functional or reporter groups onto DNA. As the enlarged cofactors are not always compatible with the active sites of native MTases, steric engineering of the active site has been employed to optimize their alkyltransferase activity. In addition to the described cofactor analogs, recently discovered atypical reactions of DNA cytosine-5 MTases involving non-cofactor-like compounds can also be exploited for targeted derivatization and labeling of DNA. Altogether, these approaches offer new powerful tools for sequence-specific covalent DNA labeling, leading to a variety of useful techniques in DNA research, diagnostics and nanotechnologies, and have already proven practical utility for optical DNA mapping and high-throughput epigenome studies.
Topics: DNA Methylation; S-Adenosylmethionine; DNA Modification Methylases; DNA; Methyltransferases
PubMed: 36350522
DOI: 10.1007/978-3-031-11454-0_19 -
The Biochemical Journal Jul 2016Methylation of biomolecules is a frequent biochemical reaction within the cell, and a plethora of highly specific methyltransferases (MTases) catalyse the transfer of a... (Review)
Review
Methylation of biomolecules is a frequent biochemical reaction within the cell, and a plethora of highly specific methyltransferases (MTases) catalyse the transfer of a methyl group from S-adenosylmethionine (AdoMet) to various substrates. The posttranslational methylation of lysine residues, catalysed by numerous lysine (K)-specific protein MTases (KMTs), is a very common and important protein modification, which recently has been subject to intense studies, particularly in the case of histone proteins. The majority of KMTs belong to a class of MTases that share a defining 'SET domain', and these enzymes mostly target lysines in the flexible tails of histones. However, the so-called seven-β-strand (7BS) MTases, characterized by a twisted beta-sheet structure and certain conserved sequence motifs, represent the largest MTase class, and these enzymes methylate a wide range of substrates, including small metabolites, lipids, nucleic acids and proteins. Until recently, the histone-specific Dot1/DOT1L was the only identified eukaryotic 7BS KMT. However, a number of novel 7BS KMTs have now been discovered, and, in particular, several recently characterized human and yeast members of MTase family 16 (MTF16) have been found to methylate lysines in non-histone proteins. Here, we review the status and recent progress on the 7BS KMTs, and discuss these enzymes at the levels of sequence/structure, catalytic mechanism, substrate recognition and biological significance.
Topics: Animals; Histone-Lysine N-Methyltransferase; Humans; Lysine; Methylation; Methyltransferases; Protein Processing, Post-Translational; Substrate Specificity
PubMed: 27407169
DOI: 10.1042/BCJ20160117 -
Protein & Cell Apr 2023Histone lysine methyltransferases (HKMTs) deposit methyl groups onto lysine residues on histones and play important roles in regulating chromatin structure and gene... (Review)
Review
Histone lysine methyltransferases (HKMTs) deposit methyl groups onto lysine residues on histones and play important roles in regulating chromatin structure and gene expression. The structures and functions of HKMTs have been extensively investigated in recent decades, significantly advancing our understanding of the dynamic regulation of histone methylation. Here, we review the recent progress in structural studies of representative HKMTs in complex with nucleosomes (H3K4, H3K27, H3K36, H3K79, and H4K20 methyltransferases), with emphasis on the molecular mechanisms of nucleosome recognition and trans-histone crosstalk by these HKMTs. These structural studies inform HKMTs' roles in tumorigenesis and provide the foundations for developing new therapeutic approaches targeting HKMTs in cancers.
Topics: Nucleosomes; Histones; Histone-Lysine N-Methyltransferase; Lysine; Methyltransferases; Methylation
PubMed: 37051671
DOI: 10.1093/procel/pwac032 -
Analytical Chemistry Mar 2022DNA methylation is catalyzed by a family of DNA methyltransferases that play crucial roles in various biological processes. Therefore, an ultrasensitive...
DNA methylation is catalyzed by a family of DNA methyltransferases that play crucial roles in various biological processes. Therefore, an ultrasensitive methyltransferase assay is highly desirable in biomedical research and clinical diagnosis. However, conventional assays for the detection of DNA methyltransferase activity often involve radioactive labeling, costly equipment, and laborious operation. In this study, an ultrasensitive and label-free method for detecting DNA adenine methyltransferase (Dam) and CpG methyltransferase (M.SssI) was developed using the nanopore technique coupled with DNA cascade signal amplification reactions. A hairpin DNA (H) comprising of the methylation-responsive sequences was skillfully designed. In the presence of Dam methyltransferase, the corresponding recognition site of hairpin H was methylated and specifically cleaved by I endonuclease, thus forming a DNA fragment that induces the catalytic hairpin assembly and hybridization chain reaction (CHA-HCR). The generated products could be absorbed onto the Zr-coated nanopore, resulting in an ion current rectification signal change. Considering the high sensitivity of the nanopore and excellent specificity toward the recognition of methyltransferase/endonuclease, our developed method could detect both Dam and M.SssI methyltransferases in the same sensing platform. Furthermore, the designed nanopore sensor could realize the multiplex detection of Dam and M.SssI methyltransferases after integration with the cascaded INHIBIT-AND logic gate. This ultrasensitive methyltransferase assay holds great promise in the field of cancer diagnosis.
Topics: Biosensing Techniques; DNA; DNA Methylation; DNA Modification Methylases; Methyltransferases; Nanopores
PubMed: 35234450
DOI: 10.1021/acs.analchem.1c05332 -
Drug Metabolism and Disposition: the... Aug 2023-methylation of drugs containing thiol-moieties often alters their activity and results in detoxification. Historically, scientists attributed methylation of exogenous...
-methylation of drugs containing thiol-moieties often alters their activity and results in detoxification. Historically, scientists attributed methylation of exogenous aliphatic and phenolic thiols to a putative -adenosyl-L-methionine (SAM)-dependent membrane-associated enzyme referred to as thiol methyltransferase (TMT). This putative TMT appeared to have a broad substrate specificity and methylated the thiol metabolite of spironolactone, mertansine, ziprasidone, captopril, and the active metabolites of the thienopyridine prodrugs, clopidogrel, and prasugrel. Despite TMT's role in the -methylation of clinically relevant drugs, the enzyme(s) responsible for this activity remained unknown. We recently identified methyltransferase-like protein 7B (METTL7B) as an alkyl thiol methyltransferase. METTL7B is an endoplasmic reticulum-associated protein with similar biochemical properties and substrate specificity to the putative TMT. Yet, the historic TMT inhibitor 2,3-dichloro--methylbenzylamine (DCMB) did not inhibit METTL7B, indicating that multiple enzymes contribute to TMT activity. Here we report that methyltransferase-like protein 7A (METTL7A), an uncharacterized member of the METTL7 family, is also a SAM-dependent thiol methyltransferase. METTL7A exhibits similar biochemical properties to METTL7B and putative TMT, including inhibition by DCMB (IC = 1.17 M). Applying quantitative proteomics to human liver microsomes and gene modulation experiments in HepG2 and HeLa cells, we determined that TMT activity correlates closely with METTL7A and METTL7B protein levels. Furthermore, purification of a novel His-GST-tagged recombinant protein and subsequent activity experiments prove that METTL7A can selectively methylate exogenous thiol-containing substrates, including 7-thiospironolactone, dithiothreitol, 4-chlorothiophenol, and mertansine. We conclude that the METTL7 family encodes for two enzymes, METTL7A and METTL7B, which are now renamed thiol methyltransferase 1A (TMT1A) and thiol methyltransferase 1B (TMT1B), respectively, that are responsible for thiol methylation activity in human liver microsomes. SIGNIFICANCE STATEMENT: We identified methyltransferase-like protein 7A (thiol methyltransferase 1A) and methyltransferase-like protein 7B (thiol methyltransferase 1B) as the enzymes responsible for the microsomal alkyl thiol methyltransferase (TMT) activity. These are the first two enzymes directly associated with microsomal TMT activity. -methylation of commonly prescribed thiol-containing drugs alters their pharmacological activity and/or toxicity, and identifying the enzymes responsible for this activity will improve our understanding of the drug metabolism and pharmacokinetic (DMPK) properties of alkyl- or phenolic thiol-containing therapeutics.
Topics: Humans; HeLa Cells; Methyltransferases; Liver; Recombinant Proteins; Sulfhydryl Compounds
PubMed: 37137720
DOI: 10.1124/dmd.123.001268