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
Symbiotic bacteria: from hitchhiker to beetle bodyguard
28.04.2017 | Johannes Gutenberg-Universität Mainz
Nose2Brain – Better Therapy for Multiple Sclerosis
28.04.2017 | Fraunhofer-Institut für Grenzflächen- und Bioverfahrenstechnik IGB
More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.
Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...
Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.
"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...
The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.
Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...
The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...
Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.
Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...
28.04.2017 | Event News
20.04.2017 | Event News
18.04.2017 | Event News
28.04.2017 | Medical Engineering
28.04.2017 | Earth Sciences
28.04.2017 | Life Sciences