Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Circadian influence in plants more widespread than previously thought

02.07.2003


While picking apart the genetic makeup of the plant Arabidopsis, two Dartmouth researchers made a startling discovery. They found that approximately 36 percent of its genome is potentially regulated by the circadian clock, which is three and a half times more than had previously been estimated.



The study, which appears in the June issue of Plant Physiology, was conducted by C. Robertson McClung, Dartmouth professor of biological sciences, and Todd Michael, a former Dartmouth graduate student who is now a postdoctoral fellow at the Salk Institute in La Jolla, Calif. Their research on circadian-controlled genes contributes to efforts to help improve plant productivity and can possibly lead to growing crops that are more resistant to stressful soil or climate conditions.

McClung and Michael used a technique called "gene trapping" or "enhancer trapping" to measure how much mRNA is produced or synthesized by large sections in the genome. According to McClung, a great deal of gene regulation occurs in the gene’s ability to synthesize mRNA, which then is translated into proteins that perform the critical metabolic activities of a cell.


In this study, the researchers randomly inserted a gene that encodes an easily measurable element, in this case luciferase (the enzyme that makes fireflies glow), into the genome to see what genes would be involved in mRNA synthesis. Luciferase is only expressed when it is inserted adjacent to an active plant gene, and it takes on that native gene’s expression. With this method the researchers found new regions of the genome under circadian control.

"In terms of clock control of mRNA synthesis, it does appear that it’s more widespread than we had estimated," says McClung. "It runs contrary to accepted dogma. It’s a new look at this from a slightly different perspective and it gives a slightly different answer. I think our study points out some of the limitations of microarray analysis."

Previous comprehensive genetic studies utilized microarray analysis and had only measured about 10% of the mRNAs in the organism showing circadian oscillations. Microarray studies look at the total abundance of mRNA, including both synthesis and degradation. McClung and Michael’s measurements focus specifically on the rate of mRNA synthesis.

Questions still remain about the discrepancy between the number of genes whose mRNA synthesis is clock regulated and the number whose mRNA abundance exhibits circadian oscillations.

"The answer might lie with the stability of mRNA; if it’s too stable, then the rhythms disappear because the vast majority of the mRNA persists, leading to a pattern of apparent continuous accumulation," says McClung. "It’s also possible that we picked up orphan circadian elements that aren’t actually regulating anything."

Sue Knapp | EurekAlert!
Further information:
http://www.dartmouth.edu/

More articles from Life Sciences:

nachricht New way to look at cell membranes could change the way we study disease
19.11.2018 | University of Oxford

nachricht Controlling organ growth with light
19.11.2018 | European Molecular Biology Laboratory

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: UNH scientists help provide first-ever views of elusive energy explosion

Researchers at the University of New Hampshire have captured a difficult-to-view singular event involving "magnetic reconnection"--the process by which sparse particles and energy around Earth collide producing a quick but mighty explosion--in the Earth's magnetotail, the magnetic environment that trails behind the planet.

Magnetic reconnection has remained a bit of a mystery to scientists. They know it exists and have documented the effects that the energy explosions can...

Im Focus: A Chip with Blood Vessels

Biochips have been developed at TU Wien (Vienna), on which tissue can be produced and examined. This allows supplying the tissue with different substances in a very controlled way.

Cultivating human cells in the Petri dish is not a big challenge today. Producing artificial tissue, however, permeated by fine blood vessels, is a much more...

Im Focus: A Leap Into Quantum Technology

Faster and secure data communication: This is the goal of a new joint project involving physicists from the University of Würzburg. The German Federal Ministry of Education and Research funds the project with 14.8 million euro.

In our digital world data security and secure communication are becoming more and more important. Quantum communication is a promising approach to achieve...

Im Focus: Research icebreaker Polarstern begins the Antarctic season

What does it look like below the ice shelf of the calved massive iceberg A68?

On Saturday, 10 November 2018, the research icebreaker Polarstern will leave its homeport of Bremerhaven, bound for Cape Town, South Africa.

Im Focus: Penn engineers develop ultrathin, ultralight 'nanocardboard'

When choosing materials to make something, trade-offs need to be made between a host of properties, such as thickness, stiffness and weight. Depending on the application in question, finding just the right balance is the difference between success and failure

Now, a team of Penn Engineers has demonstrated a new material they call "nanocardboard," an ultrathin equivalent of corrugated paper cardboard. A square...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Optical Coherence Tomography: German-Japanese Research Alliance hosted Medical Imaging Conference

19.11.2018 | Event News

“3rd Conference on Laser Polishing – LaP 2018” Attracts International Experts and Users

09.11.2018 | Event News

On the brain’s ability to find the right direction

06.11.2018 | Event News

 
Latest News

New materials: Growing polymer pelts

19.11.2018 | Materials Sciences

Earthquake researchers finalists for supercomputing prize

19.11.2018 | Information Technology

Controlling organ growth with light

19.11.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>