Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

DNA scissors can cut RNA, too

02.03.2018

The bacterial immune system “CRISPR-Cas9” is known to eliminate invading DNA. Würzburg scientists now discovered that it can also readily target RNA – a result with potentially far-reaching ramifications.

Our ability to change the content of genes at will—whether to reverse genetic diseases or improve food and energy crops—is undergoing a revolution. This revolution is being driven by “CRISPR-Cas9”, a technology based on an immune system of bacteria, discovered only a few years ago. This immune system recognizes and cuts foreign genomic material (desoxyribonucleic acid, DNA) from invading viruses and thus protects the bacteria from being infected.


From the left: Prof. Dr. Cynthia Sharma, Sara Eisenbart, Thorsten Bischler, Belinda Aul from IMIB and Prof. Dr. Chase Beisel from HIRI in Würzburg.

(Photo: Hilde Merkert, IMIB)

The cutting is performed by the Cas9 protein, that acts as a pair of scissors, while other parts of the system act as guides that instruct where Cas9 should cut the DNA. Scientists have been harnessing these molecular scissors in combination with artificial guides to specifically modify genes – not only in bacteria but also in plants and animals.

Cas9 protein is also capable of cutting RNA

While the Cas9 scissors are known to typically cut DNA, researchers from the Julius-Maximilians-Universität Würzburg (JMU) and the Helmholtz Institute for RNA-based Infection Research (HIRI), an institution of Helmholtz Centre for Infection Research, in Germany now showed that the Cas9 protein of the food-borne pathogen Campylobacter jejuni is not limited thereto.

“Instead, the protein is also capable of cutting related molecules, called ribonucleic acids – RNA, for short”, emphasizes Prof. Cynthia Sharma from the JMU Institute for Molecular Infection Biology (IMIB). “Not only that, but we found that we could also program this Cas9 to target and cut specific RNA molecules.”

RNA plays a central role in all forms of life. A major role of RNAs is to serve as messenger of genomic material in the cell: genes, specific parts of the information, stored in the DNA, are extracted by transcribing them into RNA. The RNA then serves as template for the translation of this information into proteins. The ability to target RNA instead of DNA expands how Cas9 scissors can be used. Potential uses range from controlling which genes are turned off or on to combatting human viruses that are made of RNA to rapidly detecting infectious agents.

The researchers discovered this molecular feat while looking at molecules that interact with the Cas9 in Campylobacter. These included numerous RNAs from the cell. Further analyses showed that Cas9 not only bound but could also cut the RNA in a similar way as it does with DNA – and that it could be easily instructed to cut specific RNAs.

“The finding was surprising, given that Cas9 is thought to naturally target DNA only” says Prof. Chase Beisel, who recently joined HIRI from NC State University (USA) and has been collaborating with Prof. Sharma on the project.

Possibly a general trait of Cas9 proteins

While the researchers made this finding with the Cas9 protein from Campylobacter, two other groups of researchers recently reported similar findings with Cas9s from two other bacteria. This raises the possibility that this fascinating new discovery could be a general trait of Cas9 proteins in nature.

Another question raised by this study is whether the ability of Cas9 to target RNA has any physiological roles in Campylobacter. For instance, evidence is accumulating that CRISPR-Cas systems might not only serve to combat infections, but might rather be naturally involved in controlling which genes in Campylobacter are turned on and off. Prof. Sharma and Prof. Beisel agree: “We continue to be amazed by what Cas9 is capable of doing and what new applications and technologies these insights create.”

Gaurav Dugar, Ryan T. Leenay, Sara K. Eisenbart, Thorsten Bischler, Belinda U. Aul, Chase L. Beisel, Cynthia M. Sharma: CRISPR RNA-dependent binding and cleavage of endogenous RNAs by the Campylobacter jejuni Cas9; Molecular Cell, DOI: https://doi.org/10.1016/j.molcel.2018.01.032

Contact

Prof. Dr. Cynthia M. Sharma, Chair for Molecular Infection Biology II, Institute of Molecular Infection Biology (IMIB), University of Würzburg, Phone: +49-931/31-82560, cynthia.sharma@uni-wuerzburg.de

Prof. Dr. Chase Beisel, Helmholtz Institute for RNA-based Infection Research (HIRI), Institution of Helmholtz Centre for Infection Research, Phone: 0931/31-85346, Chase.Beisel@helmholtz-hiri.de

Helmholtz Centre for Infection Research

Scientists at the Helmholtz Centre for Infection Research (HZI) in Braunschweig, Germany, are engaged in the study of different mechanisms of infection and of the body’s response to infection. Helping to improve the scientific community’s understanding of a given bacterium’s or virus’ pathogenicity is key to developing effective new treatments and vaccines. The HZI is a member of the German Center for Infection Research (DZIF). http://www.helmholtz-hzi.de/en

Robert Emmerich | Julius-Maximilians-Universität Würzburg

More articles from Life Sciences:

nachricht AI-driven single blood cell classification: New method to support physicians in leukemia diagnostics
13.11.2019 | Helmholtz Zentrum München - Deutsches Forschungszentrum für Gesundheit und Umwelt

nachricht Small RNAs link immune system and brain cells
13.11.2019 | Goethe-Universität Frankfurt am Main

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Magnets for the second dimension

If you've ever tried to put several really strong, small cube magnets right next to each other on a magnetic board, you'll know that you just can't do it. What happens is that the magnets always arrange themselves in a column sticking out vertically from the magnetic board. Moreover, it's almost impossible to join several rows of these magnets together to form a flat surface. That's because magnets are dipolar. Equal poles repel each other, with the north pole of one magnet always attaching itself to the south pole of another and vice versa. This explains why they form a column with all the magnets aligned the same way.

Now, scientists at ETH Zurich have managed to create magnetic building blocks in the shape of cubes that - for the first time ever - can be joined together to...

Im Focus: A new quantum data classification protocol brings us nearer to a future 'quantum internet'

The algorithm represents a first step in the automated learning of quantum information networks

Quantum-based communication and computation technologies promise unprecedented applications, such as unconditionally secure communications, ultra-precise...

Im Focus: Distorted Atoms

In two experiments performed at the free-electron laser FLASH in Hamburg a cooperation led by physicists from the Heidelberg Max Planck Institute for Nuclear physics (MPIK) demonstrated strongly-driven nonlinear interaction of ultrashort extreme-ultraviolet (XUV) laser pulses with atoms and ions. The powerful excitation of an electron pair in helium was found to compete with the ultrafast decay, which temporarily may even lead to population inversion. Resonant transitions in doubly charged neon ions were shifted in energy, and observed by XUV-XUV pump-probe transient absorption spectroscopy.

An international team led by physicists from the MPIK reports on new results for efficient two-electron excitations in helium driven by strong and ultrashort...

Im Focus: A Memory Effect at Single-Atom Level

An international research group has observed new quantum properties on an artificial giant atom and has now published its results in the high-ranking journal Nature Physics. The quantum system under investigation apparently has a memory - a new finding that could be used to build a quantum computer.

The research group, consisting of German, Swedish and Indian scientists, has investigated an artificial quantum system and found new properties.

Im Focus: Shedding new light on the charging of lithium-ion batteries

Exposing cathodes to light decreases charge time by a factor of two in lithium-ion batteries.

Researchers at the U.S. Department of Energy's (DOE) Argonne National Laboratory have reported a new mechanism to speed up the charging of lithium-ion...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

High entropy alloys for hot turbines and tireless metal-forming presses

05.11.2019 | Event News

Smart lasers open up new applications and are the “tool of choice” in digitalization

30.10.2019 | Event News

International Symposium on Functional Materials for Electrolysis, Fuel Cells and Metal-Air Batteries

02.10.2019 | Event News

 
Latest News

Magnets for the second dimension

12.11.2019 | Machine Engineering

New efficiency world record for organic solar modules

12.11.2019 | Power and Electrical Engineering

Non-volatile control of magnetic anisotropy through change of electric polarization

12.11.2019 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>