Nanomole Scale Screening of Fluorescent RNA-Methyltransferase Probes Enables the Discovery of METTL1 Inhibitors.

RNA methylation is a metabolic process validated for its association with various diseases, and thus, RNA methyltransferases (MTases) have become increasingly important in drug discovery. Yet, most frequently utilized RNA MTase assays are limited in their throughput and hamper this rapidly evolving field of medicinal chemistry. In this study, we describe a modular nanomole scale building block system that allowed the identification of tailored fluorescent MTase probes to unlock a broad selection of MTase drug targets for fluorescence-based binding assays.

Covalent -Adenosylhomocysteine-Based DNA Methyltransferase 2 Inhibitors with a New Type of Aryl Warhead.

The DNA methyltransferase 2 (DNMT2) is an RNA modifying enzyme associated with pathophysiological processes, such as mental and metabolic disorders or cancer. Although the development of methyltransferase inhibitors remains challenging, DNMT2 is not only a promising target for drug discovery, but also for the development of activity-based probes. Here, we present covalent SAH-based DNMT2 inhibitors decorated with a new type of aryl warhead.

Chemical Space Virtual Screening against Hard-to-Drug RNA Methyltransferases DNMT2 and NSUN6.

Targeting RNA methyltransferases with small molecules as inhibitors or tool compounds is an emerging field of interest in epitranscriptomics and medicinal chemistry. For two challenging RNA methyltransferases that introduce the 5-methylcytosine (mC) modification in different tRNAs, namely DNMT2 and NSUN6, an ultra-large commercially available chemical space was virtually screened by physicochemical property filtering, molecular docking, and clustering to identify new ligands for those enzymes. Novel chemotypes binding to DNMT2 and NSUN6 with affinities down to K = 37 µM and K = 12 µM, respectively, were identified using a microscale thermophoresis (MST) binding assay.

An Optimized Microscale Thermophoresis Method for High-Throughput Screening of DNA Methyltransferase 2 Ligands.

Developing methyltransferase inhibitors is challenging, since most of the currently used assays are time-consuming and cost-intensive. Therefore, efficient, fast, and reliable methods for screenings and affinity determinations are of utmost importance. Starting from a literature-known fluorescent -adenosylhomocysteine derivative, 5-FAM-triazolyl-adenosyl-Dab, developed for a fluorescence polarization assay to investigate the histone methyltransferase mixed-lineage leukemia 1, we herein describe the applicability of this compound as a fluorescent tracer for the investigation of DNA-methyltransferase 2 (DNMT2), a human RNA methyltransferase.

[Bioinformatic analysis of potential post-translational modification sites of the human O6-methylguanine-DNA methyltransferase (MGMT) protein].

Using in silico analysis a number of potential sites for post-translational modifications has been revealed within the human O6-methylguanine-DNA methyltransferase (MGMT) protein. In particular these were the acetylation of Gly3 residue in the N-terminus of protein and internal residues Lys132 and Lys135; Arg166 residue methylation; Lys63 SUMOylation and ubiquitination of Lys31, Lys39, Lys49, Lys63, Lys67, Lys135, Lys156, Lys196, Lys209. Also it has been predicted 16 novel potential phosphorylation sites of serine residues (positions 13, 124, 144, 182, 183, 190, 215, 216 and 230), tyrosine residues (positions 100 and 189) and threonine residues (positions 23, 69, 94, 126 and 229), as well as five binding sites for kinases and other proteins (Serl3 with 14-3-3, Val21 and Ile172 with D-domain, Pro78 and Pro111 with SH3-domain, Pro111 with MAPK3).