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 Single-stranded DNA and RNA origami go live
15.12.2017 | Wyss Institute for Biologically Inspired Engineering at Harvard

nachricht New antbird species discovered in Peru by LSU ornithologists
15.12.2017 | Louisiana State University

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: First-of-its-kind chemical oscillator offers new level of molecular control

DNA molecules that follow specific instructions could offer more precise molecular control of synthetic chemical systems, a discovery that opens the door for engineers to create molecular machines with new and complex behaviors.

Researchers have created chemical amplifiers and a chemical oscillator using a systematic method that has the potential to embed sophisticated circuit...

Im Focus: Long-lived storage of a photonic qubit for worldwide teleportation

MPQ scientists achieve long storage times for photonic quantum bits which break the lower bound for direct teleportation in a global quantum network.

Concerning the development of quantum memories for the realization of global quantum networks, scientists of the Quantum Dynamics Division led by Professor...

Im Focus: Electromagnetic water cloak eliminates drag and wake

Detailed calculations show water cloaks are feasible with today's technology

Researchers have developed a water cloaking concept based on electromagnetic forces that could eliminate an object's wake, greatly reducing its drag while...

Im Focus: Scientists channel graphene to understand filtration and ion transport into cells

Tiny pores at a cell's entryway act as miniature bouncers, letting in some electrically charged atoms--ions--but blocking others. Operating as exquisitely sensitive filters, these "ion channels" play a critical role in biological functions such as muscle contraction and the firing of brain cells.

To rapidly transport the right ions through the cell membrane, the tiny channels rely on a complex interplay between the ions and surrounding molecules,...

Im Focus: Towards data storage at the single molecule level

The miniaturization of the current technology of storage media is hindered by fundamental limits of quantum mechanics. A new approach consists in using so-called spin-crossover molecules as the smallest possible storage unit. Similar to normal hard drives, these special molecules can save information via their magnetic state. A research team from Kiel University has now managed to successfully place a new class of spin-crossover molecules onto a surface and to improve the molecule’s storage capacity. The storage density of conventional hard drives could therefore theoretically be increased by more than one hundred fold. The study has been published in the scientific journal Nano Letters.

Over the past few years, the building blocks of storage media have gotten ever smaller. But further miniaturization of the current technology is hindered by...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

See, understand and experience the work of the future

11.12.2017 | Event News

Innovative strategies to tackle parasitic worms

08.12.2017 | Event News

AKL’18: The opportunities and challenges of digitalization in the laser industry

07.12.2017 | Event News

 
Latest News

Engineers program tiny robots to move, think like insects

15.12.2017 | Power and Electrical Engineering

One in 5 materials chemistry papers may be wrong, study suggests

15.12.2017 | Materials Sciences

New antbird species discovered in Peru by LSU ornithologists

15.12.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>