title: Identification of small-molecule inhibitors of the ribonuclease H2 enzyme.
abstract: Ribonuclease H2 (RNase H2) is a nuclease that specifically hydrolyzes RNA residues in RNA-DNA hybrids. Mutations in the RNase H2 enzyme complex have been identified in the genetic disorder Aicardi-Goutières syndrome (AGS), which has similarities to the autoimmune disease systemic lupus eryrthrematosis (SLE). The RNase H2 enzyme has also been recently implicated as a key genome surveillance enzyme. Therefore, small-molecule modulators of RNase H2 activity may have utility in therapeutics and as tools to investigate the cellular functions of RNase H2. A fluorescent quench assay, measuring cleavage of an RNA-DNA duplex substrate by recombinant RNase H2, was developed into a high-throughput format and used to screen a 48 560 compound library. A hit validation strategy was subsequently employed, leading to the identification of two novel inhibitor compounds with in vitro nanomolar range inhibition of RNase H2 activity and >100-fold selectivity compared with RNase H type 1. These compounds are the first small-molecule inhibitors of RNase H2 to be reported. They and their derivatives should provide the basis for the development of tool compounds investigating the cellular functions of the RNase H2 enzyme, and, potentially, for pharmacological manipulation of nucleic acid-mediated immune responses.
authors: MRC Human Genetics Unit, MRC IGMM, University of Edinburgh, Edinburgh, UK.
authors: Rachel
authors: R
authors: White
authors: Barbara
authors: B
authors: Saxty
authors: Jonathan
authors: J
authors: Large
authors: Catherine A
authors: CA
authors: Kettleborough
authors: Andrew P
authors: AP
authors: Jackson
mesh_terms: D002470:Cell Survival / Q000187:drug effects; D055808:Drug Discovery / Q000379:methods; D004353:Drug Evaluation, Preclinical; D004791:Enzyme Inhibitors / Q000302:isolation & purification* / Q000494:pharmacology; D031541:Fluorescence Resonance Energy Transfer / Q000379:methods; D006367:HeLa Cells; D057166:High-Throughput Screening Assays / Q000379:methods*; D006801:Humans; D008856:Microscopy, Fluorescence; D008954:Models, Biological; D016914:Ribonuclease H / Q000037:antagonists & inhibitors*; D054852:Small Molecule Libraries / Q000032:analysis; D054928:Validation Studies as Topic
chemical_list: D004791:Enzyme Inhibitors; D054852:Small Molecule Libraries; C091139:ribonuclease HII; D016914:Ribonuclease H
keywords: Aicardi-Goutières syndrome; high-throughput screen; inhibitors; nuclease; ribonuclease H2