Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Corn Researchers Discover Novel Gene Shut-off Mechanisms

03.11.2008
University of Delaware scientists, in collaboration with researchers from the University of Arizona and South Dakota State University, have identified unusual differences in the natural mechanisms that turn off, or “silence,” genes in corn.

The discovery, which was made by comparing the impact of inactivating a gene that occurs in both corn and in the much-studied laboratory plant Arabidopsis, provides new insight into how one of the world's most important crops protects itself from mutation-causing mobile DNA elements and viruses.

The research was led by Blake Meyers, associate professor of plant and soil sciences, and Pamela Green, Crawford H. Greenewalt Chair and professor of plant and soil sciences and marine bioscience, and their laboratory groups at the Delaware Biotechnology Institute, a major center for biotechnology and life sciences research at the University of Delaware.

Collaborating with the University of Delaware team were Vicki Chandler, the Carl E. and Patricia Weiler Endowed Chair for Excellence in Agriculture and Life Sciences Regents' Professor at the University of Arizona, and Yang Yen, a professor at South Dakota State University.

... more about:
»Arabidopsis »Corn »MOP1 »RDR2 »RNA »RNA polymerase 2

The results were published in the Proceedings of the National Academy of Sciences of the United States of America.

Studies of Arabidopsis thaliana, a small flowering plant of the mustard family that is easy to grow in the lab, have provided a lot of what scientists know about gene silencing in plants.

An important key to the process is short sequences of ribonucleic acids known as “small RNAs” which act like biochemical switches that shut off genes, thus playing a fundamental role in plant development. Understanding how small RNAs work is a continuing quest for geneticists seeking to breed plants with improved crop yields, disease resistance and other characteristics.

Previously, the Meyers and Green labs had studied Arabidopsis plants with nonfunctional versions of a gene known as RNA-dependent RNA polymerase 2 (RDR2). Without an active copy of this gene, the plants were unable to produce a major class of small RNAs, which act to stabilize and protect genes on the chromosomes.

In that prior work, Meyers and Green took advantage of the nonfunctional gene to study microRNAs, an interesting type of small RNA that is usually “masked” by the major class of small RNAs produced by RDR2.

Independently of the UD groups, Chandler and her team at the University of Arizona had identified from corn an orthologous gene--a gene that has the same function in different organisms. In corn, this gene, which the Chandler lab found, is called the mediator of paramutation (MOP1). Its equivalent in Arabidopsis is the RDR2 gene.

Because the RDR2 and MOP1 genes should both produce the “protective” set of small RNAs, the research groups decided to collaborate to see if the small RNAs in corn behave the same way they do in Arabidopsis. The hypothesis was that the result would be the same in the two plant species, and the lab groups could use the MOP1 corn plants to focus their studies on the harder-to-examine microRNAs, as they had done previously in Arabidopsis.

“Yet we found something that had not been observed before in this plant--an odd class of small RNAs,” Meyers said. “I think it's pretty neat to work in a more complex system like corn and see things that Arabidopsis hadn't shown us,” he noted.

Using a technique known as sequencing by synthesis (SBS), provided by Illumina in Hayward, Calif., coupled with state-of-the-art bioinformatics in Meyers' lab, the research team found that the MOP1 and RDR2 genes are not fully equivalent based on an assessment of small RNA complexity.

The researchers found that there are lots more RNAs of an unusual class known as “small interfering RNAs” in corn than there are in Arabidopsis.

“This class of RNAs mainly functions to repress repetitive sequences, including mobile DNA elements called transposons,” Meyers said. “Thus, small interfering RNAs act to protect the genome,” he noted.

“Corn contains an extra layer of protective small RNAs that had not been observed in Arabidopsis, so there must be additional genes other than MOP1 that produce this,” Meyers said.

The scientific community is sequencing the corn genome now, Meyers said. Once the genome is available, the work of matching up small RNAs to specific traits in corn will be much easier, he noted.

“This research is helping us to better understand the biology of corn--one of the most important plants in the world--and gives us new avenues for exploring a novel class of small RNAs,” Meyers said.

View the release at http://www.udel.edu/udaily/2009/oct/corn103008.html

Tracey Bryant | Newswise Science News
Further information:
http://www.udel.edu
http://www.udel.edu/udaily/2009/oct/corn103008.html

Further reports about: Arabidopsis Corn MOP1 RDR2 RNA RNA polymerase 2

More articles from Agricultural and Forestry Science:

nachricht Climate change, population growth may lead to open ocean aquaculture
05.10.2017 | Oregon State University

nachricht New machine evaluates soybean at harvest for quality
04.10.2017 | University of Illinois College of Agricultural, Consumer and Environmental Sciences

All articles from Agricultural and Forestry Science >>>

The most recent press releases about innovation >>>

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

Im Focus: Neutron star merger directly observed for the first time

University of Maryland researchers contribute to historic detection of gravitational waves and light created by event

On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...

Im Focus: Breaking: the first light from two neutron stars merging

Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.

Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....

Im Focus: Smart sensors for efficient processes

Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).

When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...

Im Focus: Cold molecules on collision course

Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.

How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...

Im Focus: Shrinking the proton again!

Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.

It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ASEAN Member States discuss the future role of renewable energy

17.10.2017 | Event News

World Health Summit 2017: International experts set the course for the future of Global Health

10.10.2017 | Event News

Climate Engineering Conference 2017 Opens in Berlin

10.10.2017 | Event News

 
Latest News

Electrode materials from the microwave oven

19.10.2017 | Materials Sciences

New material for digital memories of the future

19.10.2017 | Materials Sciences

Physics boosts artificial intelligence methods

19.10.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>