Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Antagonistic genes control rice growth

17.12.2009
Scientists at the Carnegie Institution, with colleagues,* have found that a plant steroid prompts two genes to battle each other—one suppresses the other to ensure that leaves grow normally in rice and the experimental plant Arabidopsis thaliana, a relative of mustard. The results, published in the December 15, 2009, issue of The Plant Cell, have important implications for understanding how to manipulate crop growth and yield.

In plants, steroid levels reflect environmental and internal signals and control many processes. Steroid hormones called brassinosteroids (BRs) start their action on the surface of the cell and, through a molecular relay, send signals into the cell's nucleus to turn on or off specific genes, particularly those that are critical to regulating plant growth and development. Although a lot has been discovered about how the steroid affects genes in Arabidopsis, much less was known in crop plants such as rice.

Co-author Zhi-Yong Wang at Carnegie's Department of Plant Biology explained the work: "We knew that the steroid is very important for activating genes that control cell growth in Arabidopsis as well as in rice. One of the most sensitive responses to the steroid is leaf bending in rice, caused by expansion of the upper cells at the joint between leaf blade and leaf sheath. We wanted to determine how the steroid functioned in rice. We found that the steroid affects two genes encoding (or producing) proteins that turn other genes on or off; they are called transcription factors. In rice, when a gene called Increased Leaf Inclination1 (ILI1) is turned on, it causes leaf bending. Interestingly, we found that the ILI1 protein also binds to another transcription factor, called IBH1, and inhibits its function. When there is too much ILI1 protein, the leaves bend excessively making the plant shaggy. When IBH1 level is high, cell growth is stopped at the joint and the rice is very erect, taking up less space. In normal rice plants the balance between ILI1 and IBH1 keeps growth in check."

This pair of genes provides a unique tool to control the leaf angle, which is important for crop yield because erect leaves improve light capture and allows rice plants to be planted at higher density for a higher yield per hectare.

Through a series of experiments, the researchers determined how the steroid and genes interact. They found that brassinosteroid oppositely regulate these genes—ILI1 was activated and IBH1 was repressed. As such, the steroid tips the balance between their protein products, ILI1 and IBH1, to initiate cell growth.

"It appears that the steroid causes the IBH1 genes to stop the production of IBH1 protein, and in the meantime increases the production of the ILI1 protein, which turns off IBH1's inhibition of cell growth. This ensures that the cell grows to just the right length according to the level of steroid," commented Wang.

The researchers performed similar experiments on the mustard, which showed that steroid interacted with the mustard genes the same way. "Since similar genes are doing the same thing in these different plants, this process is likely to be very old and found in many different higher plants. The more we learn about such mechanisms, the closer we will come to better engineering crops to feed a growing population," concluded Wang.

The work was supported by the National Science Foundation of China; The National Institute of Health; the Ministry of Education, Culture, Sports, Science and Technology of Japan; and the Carnegie Institution.

*Colleagues on the study are from the following institutions: Institute of Botany, Chinese Academy of Sciences; Chinese Academy of Agricultural Sciences; Department of Plant Biology, Carnegie Institution; Yonsei University, Korea; RIKEN Advanced Science Institute, Japan.

The Carnegie Institution for Science (www.CIW.edu) has been a pioneering force in basic scientific research since 1902. It is a private, nonprofit organization with six research departments throughout the U.S. Carnegie scientists are leaders in plant biology, developmental biology, astronomy, materials science, global ecology, and Earth and planetary science.

Zhi-Yong Wang | EurekAlert!
Further information:
http://www.ciw.edu

More articles from Life Sciences:

nachricht The birth of a new protein
20.10.2017 | University of Arizona

nachricht Building New Moss Factories
20.10.2017 | Albert-Ludwigs-Universität Freiburg im Breisgau

All articles from Life Sciences >>>

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

Terahertz spectroscopy goes nano

20.10.2017 | Information Technology

Strange but true: Turning a material upside down can sometimes make it softer

20.10.2017 | Materials Sciences

NRL clarifies valley polarization for electronic and optoelectronic technologies

20.10.2017 | Interdisciplinary Research

VideoLinks
B2B-VideoLinks
More VideoLinks >>>