“Structure determination of RNA-dependent RNA Polymerase 2 (RDR2) by cryo-EM and its implications for double-stranded RNA synthesis in gene silencing”
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Date:
4:00 PM – 5:30 PM Tuesday, December 19th, 2023 (JST),
Location: Hybrid (CryoEM-Lab KEK and Zoom)
Speaker
Yuichiro H. Takagi, Ph.D.
Associate Professor
Scientific advisor for cryo-EM
Department of Biochemistry and Molecular Biology
Indiana University School of Medicine
Abstract
RNA-dependent RNA polymerases (RdRP) play critical roles in RNA-mediated gene silencing. In Arabidopsis thaliana, RNA-Dependent RNA Polymerase 2 (RDR2) generates double-stranded RNAs (dsRNAs) from a single stranded RNA template generated by DNA-dependent nuclear RNA Polymerase IV (Pol IV). Resulting dsRNAs are then processed into short-interfering RNAs that guide RNA-directed DNA methylation and transcriptional gene silencing. We determined the structure of RDR2 at 3.1 Å resolution by single-particle cryo-electron microscopy. The structure suggests its implications for double-stranded RNA synthesis in gene silencing. The seminar will also touch on several structure examples determined by Takagi lab using cryo-EM including Mediator CDK8 module from the yeast Saccharomyces cerevisiae, human asparagine synthetase, and multicopper oxidase from Marinithermus hydrothermalis.