Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

UGA researchers edit plant DNA using mechanism evolved in bacteria

05.06.2015

Researchers at the University of Georgia have used a gene editing tool known as CRISPR/Cas to modify the genome of a tree species for the first time. Their research, published recently in the early online edition of the journal New Phytologist, opens the door to more rapid and reliable gene editing of plants.

By mutating specific genes in Populus--a genus of deciduous trees that includes poplar, aspen and cottonwood--the researchers reduced the concentrations of two naturally occurring plant polymers.


Poplar plants produced from a lignin-gene-targeting experiment in C.J. Tsai's lab at the University of Georgia had red-colored wood. Red stem is a known side effect of lignin modification, so the researchers knew the CRISPR system worked when they saw the red stems on their plants.

Credit: University of Georgia

One is called lignin, which traps sugars and starches used for biofuel production inside the tree's sturdy cell walls. The other is known as condensed tannin, and its presence in leaves and barks of the tree deters feeding by ruminants, such as deer, cattle, goats and sheep.

"CRISPR is a relatively new technology, but it could improve our ability to produce novel varieties of food crops, animal feeds and biofuel feedstocks," said the study's lead researcher C.J. Tsai, a Georgia Research Alliance Eminent Scholar in UGA's Warnell School of Forestry and Natural Resources and department of genetics. "Compared to some other gene editing techniques, this is incredibly simple, cost-effective and highly efficient, and it could serve as the foundation for a new era of discovery in plant genetics."

CRISPR technology is derived from a defense mechanism evolved by bacteria and other single-celled organisms. When a bacterium is attacked by an invader like a virus, it captures some of the virus's DNA, chops it up into pieces and incorporates a segment of the viral DNA into its own genome.

As the bacterium experiences more threats, it accumulates a bank of past infections in a special part of its genetic code called CRISPRs--short for clustered regularly interspaced short palindromic repeats--which act as a kind of immune system to protect against future invasions.

"This is a mechanism that evolved naturally, but we can borrow the bacteria's gene-cutting abilities and use it to edit very specific genes in all kinds of organisms, including plants and animals," said Tsai, who is also director of UGA's Plant Center. "It's like using a pair of scissors with GPS tracking to locate and snip out tiny bits of DNA--enough to nullify the gene you don't want, while leaving everything else unchanged."

Tsai credits her collaborator Thomas Jacobs, a former doctoral student in UGA's Institute of Plant Breeding, Genetics and Genomics, who adapted the CRISPR system for plant genome editing.

"Tom was a student in my class a few years back, and we were testing some of the gene silencing systems he developed for soybean in poplars," Tsai said. "It was a side project, also involving Xiaohong Zhou, a visiting doctoral student from Nanjing Forestry University, to test the new CRISPR system, and its high efficiency exceeded all of our expectations."

Every single poplar plant Zhou produced from the lignin-gene-targeting experiment had red-colored wood. Red stem is a known side effect of lignin modification found in natural mutants of maize, sorghum and pine, Tsai explained, so the researchers knew the CRISPR system worked when they saw the telltale red stems on their Populus plants.

"I was blown away by the results," Jacobs said. "This is one of the highest efficiencies ever reported, even in mouse and other animal models where the technology has been more extensively tested."

The modified Populus plants contained about 20 percent less lignin and 50 percent less condensed tannins than wild trees.

"We thought we knew what genes control lignin and condensed tannin production, and we did target the right genes, but the work showed us that there are other genes with overlapping roles," Tsai said. "The CRISPR system can now guide researchers seeking to identify these previously unknown gene family members."

###

The article on "Exploiting SNPs for biallelic CRISPR mutations in the outcrossing woody perennial Populus reveals 4-coumarate:CoA ligase specificity and redundancy" is available online at http://onlinelibrary.wiley.com/doi/10.1111/nph.13470/abstract.

Media Contact

C.J. Tsai
cjtsai@uga.edu
706-542-1271

 @universityofga

http://www.uga.edu 

C.J. Tsai | EurekAlert!

Further reports about: CRISPR DNA GPS tracking Tsai UGA bacteria bacterium biofuel production genes genetic code poplar specific genes

More articles from Life Sciences:

nachricht Ion treatments for cardiac arrhythmia — Non-invasive alternative to catheter-based surgery
20.01.2017 | GSI Helmholtzzentrum für Schwerionenforschung GmbH

nachricht Seeking structure with metagenome sequences
20.01.2017 | DOE/Joint Genome Institute

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Traffic jam in empty space

New success for Konstanz physicists in studying the quantum vacuum

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...

Im Focus: How gut bacteria can make us ill

HZI researchers decipher infection mechanisms of Yersinia and immune responses of the host

Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...

Im Focus: Interfacial Superconductivity: Magnetic and superconducting order revealed simultaneously

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...

Im Focus: Studying fundamental particles in materials

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...

Im Focus: Designing Architecture with Solar Building Envelopes

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...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Sustainable Water use in Agriculture in Eastern Europe and Central Asia

19.01.2017 | Event News

12V, 48V, high-voltage – trends in E/E automotive architecture

10.01.2017 | Event News

2nd Conference on Non-Textual Information on 10 and 11 May 2017 in Hannover

09.01.2017 | Event News

 
Latest News

Helmholtz International Fellow Award for Sarah Amalia Teichmann

20.01.2017 | Awards Funding

An innovative high-performance material: biofibers made from green lacewing silk

20.01.2017 | Materials Sciences

Ion treatments for cardiac arrhythmia — Non-invasive alternative to catheter-based surgery

20.01.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>