Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

RNA-based drugs give more control over gene editing

17.11.2015

CRISPR/Cas9 gene editing technique can be transiently activated and inactivated using RNA-based drugs, giving researchers more precise control in correcting and inactivating genes

In just the past few years, researchers have found a way to use a naturally occurring bacterial system known as CRISPR/Cas9 to inactivate or correct specific genes in any organism. CRISPR/Cas9 gene editing activity runs continuously, though, leading to risk of additional editing at unwanted sites. Now, researchers at University of California, San Diego School of Medicine, Ludwig Cancer Research and Isis Pharmaceuticals demonstrate a commercially feasible way to use RNA to turn the CRISPR-Cas9 system on and off as desired -- permanently editing a gene, but only temporarily activating CRISPR-Cas9. The study is published November 16 by Proceedings of the National Academy of Sciences.


The conventional CRISPR-Cas9 system comprises two parts: the Cas9 enzyme, which acts like a wrench, and specific RNA guides (CRISPRs), which act as different socket heads. These RNAs guide the Cas9 protein to the target gene on a DNA strand. This technique allows researchers to study genes in a specific, targeted way.

Credit: Ernesto del Aguila III, NHGRI

"These findings provide a platform for multiple therapeutic applications, especially for nervous system diseases, using successive application of designer CRISPR RNA drugs," said senior author Don Cleveland, PhD, Distinguished Professor and Chair of the Department of Cellular and Molecular Medicine at UC San Diego School of Medicine and head of Ludwig Cancer Research's Laboratory for Cell Biology.

CRISPR/Cas9 works like this: researchers design a "guide" RNA to match the sequence of a specific target gene. The RNA guides the Cas9 enzyme to the desired spot, where it cuts the DNA. The cell can repair the DNA break, but it does so imprecisely, thereby inactivating the gene. Alternatively, researchers can coax the cell into replacing the section adjacent to the cut with a healthier version of the gene. Researchers are now testing the CRISPR/Cas9 system in a variety of applications to repair defective genes that cause disease.

The new approach introduces chemically modified, RNA-based drugs to transiently activate the CRISPR/Cas9 gene editing system. An initial, specially modified RNA is used to replace the usual guide RNA. This RNA directs Cas9's DNA-cutting activity to a selected target gene and the editing process proceeds. Activity is transient, however, as the editing stops when the guiding RNA drug is cleared. An extension of the approach can switch off the molecular scissors even faster by addition of a second, chemically modified RNA drug that directs inactivation of the gene encoding the Cas9 enzyme.

"The RNA-based drugs we developed in this study provide many advantages over the current CRISPR/Cas9 system, such as increased editing efficiency and potential selectivity," said Cleveland. "In addition, they can be synthesized efficiently, on an industrial scale and in a commercially feasible manner today."

"Today's published work is another demonstration of the successful synergy between Dr. Cleveland's lab and my team at Isis Pharmaceuticals," said C. Frank Bennet, PhD, co-senior author of the study and senior vice president of research at Isis Pharmaceuticals. "Leveraging Isis' expertise in developing RNA-targeted compounds, together the team has demonstrated that we can develop molecules that enhance the effectiveness of the CRISPR mechanism."

###

Study co-authors include Meghdad Rahdar, Thazha P. Prakash, Eric E. Swayze, Isis Pharmaceuticals; Moira A. McMahon, Ludwig Cancer Research and UC San Diego.

This research was funded, in part, by the National Institutes of Health (grants R01-GM 074150, R01-NS27036 and F32-GM109657). Cleveland is a paid consultant of Isis Pharmaceuticals.

Full study: http://doi.org/10.1073/pnas.1520883112

Media Contact

Heather Buschman
hbuschman@ucsd.edu
619-543-6163

 @UCSanDiego

http://www.ucsd.edu 

Heather Buschman | EurekAlert!

Further reports about: CRISPR Cas9 DNA Medicine RNA drugs enzyme industrial scale nervous system

More articles from Life Sciences:

nachricht Newly designed molecule binds nitrogen
23.02.2018 | Julius-Maximilians-Universität Würzburg

nachricht Atomic Design by Water
23.02.2018 | Max-Planck-Institut für Eisenforschung GmbH

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Attoseconds break into atomic interior

A newly developed laser technology has enabled physicists in the Laboratory for Attosecond Physics (jointly run by LMU Munich and the Max Planck Institute of Quantum Optics) to generate attosecond bursts of high-energy photons of unprecedented intensity. This has made it possible to observe the interaction of multiple photons in a single such pulse with electrons in the inner orbital shell of an atom.

In order to observe the ultrafast electron motion in the inner shells of atoms with short light pulses, the pulses must not only be ultrashort, but very...

Im Focus: Good vibrations feel the force

A group of researchers led by Andrea Cavalleri at the Max Planck Institute for Structure and Dynamics of Matter (MPSD) in Hamburg has demonstrated a new method enabling precise measurements of the interatomic forces that hold crystalline solids together. The paper Probing the Interatomic Potential of Solids by Strong-Field Nonlinear Phononics, published online in Nature, explains how a terahertz-frequency laser pulse can drive very large deformations of the crystal.

By measuring the highly unusual atomic trajectories under extreme electromagnetic transients, the MPSD group could reconstruct how rigid the atomic bonds are...

Im Focus: Developing reliable quantum computers

International research team makes important step on the path to solving certification problems

Quantum computers may one day solve algorithmic problems which even the biggest supercomputers today can’t manage. But how do you test a quantum computer to...

Im Focus: In best circles: First integrated circuit from self-assembled polymer

For the first time, a team of researchers at the Max-Planck Institute (MPI) for Polymer Research in Mainz, Germany, has succeeded in making an integrated circuit (IC) from just a monolayer of a semiconducting polymer via a bottom-up, self-assembly approach.

In the self-assembly process, the semiconducting polymer arranges itself into an ordered monolayer in a transistor. The transistors are binary switches used...

Im Focus: Demonstration of a single molecule piezoelectric effect

Breakthrough provides a new concept of the design of molecular motors, sensors and electricity generators at nanoscale

Researchers from the Institute of Organic Chemistry and Biochemistry of the CAS (IOCB Prague), Institute of Physics of the CAS (IP CAS) and Palacký University...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

2nd International Conference on High Temperature Shape Memory Alloys (HTSMAs)

15.02.2018 | Event News

Aachen DC Grid Summit 2018

13.02.2018 | Event News

How Global Climate Policy Can Learn from the Energy Transition

12.02.2018 | Event News

 
Latest News

Basque researchers turn light upside down

23.02.2018 | Physics and Astronomy

Finnish research group discovers a new immune system regulator

23.02.2018 | Health and Medicine

Attoseconds break into atomic interior

23.02.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>