How does single "RISC" accurately cleave and release target RNAs?
University of Tokyo and Kyoto University researchers have revealed the molecular mechanism of RNA interference (RNAi), the phenomenon by which the synthesis of a specific protein is inhibited, by real time observation of target RNA cleavage at the single-molecule level.
Shedding light on the single target cleavage reaction in RNAi. The target RNA cleavage reaction by the RNAi effector complex RISC was monitored in real time at the single-molecule level by using a special microscope. This illustration represents this process. © 2015 Hachiro Hongo and Hisashi Tadakuma.
The phenomenon of RNAi is expected to find applications in medical treatments. RNAi is mediated by RNA-induced silencing complex (RISC), which contains a small RNA and an Argonaute protein at its core and cleaves the target RNA.
However, there were no suitable tools to directly monitor the RNAi reaction and its molecular mechanism by which RISC cleaves the target RNA has remained unclear.
Now, a research group at the University of Tokyo (Professor Takuya Ueda, Professor Yukihide Tomari, Researcher Chunyan Yao and Research Associate Hiroshi M Sasaki,) and at Kyoto University (Researcher Hisashi Tadakuma), has developed a single-molecule imaging assay for observing target RNA cleavage by RISC in a test tube in real time for the first time, showing how RISC accurately cleaves and releases targets.
Specifically, their obsercations provide direct evidence for the model that the small RNA in the RISC consists of two parts, one of which quickly binds to the target RNA to be cleaved, while the other proofreads that the correct RNA has been found.
This groundbreaking result reveals RISC’s molecular mechanism of action and the illustration of this process was adopted as the cover design of this issue of the journal.
This achievement will also contribute to accelerating the research applications of RNAi such as to the development of RNA-based next-generation drugs, for example as gene therapy to suppress the production of a disease-causing protein.
Chunyan Yao, Hiroshi M Sasaki, Takuya Ueda, Yukihide Tomari and Hisashi Tadakuma, "Single-molecule analysis of the target cleavage reaction by Drosophila RNAi enzyme complex", Molecular Cell Online Edition: 2015/7/3 (Japan time), doi: 10.1016/j.molcel.2015.05.015.
U Tokyo Research article
Euan McKay | ResearchSEA
Ion treatments for cardiac arrhythmia — Non-invasive alternative to catheter-based surgery
20.01.2017 | GSI Helmholtzzentrum für Schwerionenforschung GmbH
Seeking structure with metagenome sequences
20.01.2017 | DOE/Joint Genome Institute
An important step towards a completely new experimental access to quantum physics has been made at University of Konstanz. The team of scientists headed by...
Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...
Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.
While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...
Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales
Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...
Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.
As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...
19.01.2017 | Event News
10.01.2017 | Event News
09.01.2017 | Event News
20.01.2017 | Awards Funding
20.01.2017 | Materials Sciences
20.01.2017 | Life Sciences