Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Gene interactions control circadian clock in plants, study finds


David Somers

New research identifies the molecular mechanisms that keep a plant’s circadian clock running on a 24-hour schedule.

The study, reported this week in the journal Nature, is the first to describe the physical connection between two molecular components -– genes called TOC1 and ZTL -- that keep a plant’s “clock” running at the right speed. Scientists have spent more than a decade trying to understand the interactions between the components that regulate a plant’s timing.

Knowing how those components interact might benefit agriculture, as the clock controls activities like flowering time in plants, said David Somers, a study co-author and an assistant professor of plant biology at Ohio State University.

"Understanding how the clock works on the molecular level means that we can begin to understand, and perhaps manipulate, when a plant flowers," he said. "One potential limitation to where plants can grow is day length – some plants need more exposure to light than do others.

"If we could make a plant flower earlier in the growing season – assuming that temperatures were warm enough – we could possibly extend that plant’s range into a region in which it normally had difficulty growing."

Somers conducted the study with Woe-Yoon Kim, a postdoctoral researcher in plant biotechnology at Ohio State, and Paloma Más and Steve Kay, both with the Scripps Research Institute in La Jolla, Calif.

The researchers conducted experiments on Arabidopsis thaliana, or thale cress plants. They looked at plants with normal TOC1 and ZTL genes and also at Arabidopsis plants with either a mutant TOC1 or ZTL gene. Observing changes in mutant strains gave the researchers information on each gene’s involvement in regulating the circadian clock.

"We wanted to know what keeps a plant’s circadian clock running at the right speed," Somers said.

A faulty TOC1 gene caused the plants to run on a faster schedule – their circadian clocks had sped up to 20 hours. Conversely, mutations in the ZTL gene slowed the clock down to 27 hours. If both genes were missing entirely, the clock still ran, but at the wrong speed.

The researchers also looked for, and found, a strong physical interaction between TOC1 and ZTL.

"It became clear that ZTL is heavily involved in controlling the level of TOC1 in the plants," Somers said. "ZTL degrades TOC1, and this degradation is vital for normal plant functioning.

"We knew that TOC1 was one of the main components in controlling the clock’s pace," he continued. "Now we know that ZTL indirectly controls the clock’s pace through its effect on TOC1 degradation."

These findings help shed light on mechanisms that have puzzled scientists for years.

"The molecular components of the plant clock aren’t well understood," Somers said. "And, unlike the mammalian circadian clock, a lot of the individual players are still unidentified."

Just as in animals, plants’ circadian clocks are set by light and dark cycles, Somers said. In humans, feeling sleepy close to bedtime is controlled in part by the clock. In plants, the circadian clock controls the production of enzymes and other components involved in photosynthesis.

"If a plant can anticipate sunrise, it can have the necessary photosynthetic compounds prepared in advance," said Somers. "Many of the enzymes and molecular components of photosynthesis have to be re-made daily, as harvesting sunlight and turning it into useful energy is a destructive process.

"It’s to a plant’s advantage to be ready to absorb sunlight when it becomes available."

The study was funded by grants from the National Institutes of Health and the National Science Foundation.

Contact: David Somers, (614) 292-2551;
Written by Holly Wagner, (614) 292-8310;

Holly Wagner | OSU
Further information:

More articles from Life Sciences:

nachricht Biologists unravel another mystery of what makes DNA go 'loopy'
16.03.2018 | Emory Health Sciences

nachricht Scientists map the portal to the cell's nucleus
16.03.2018 | Rockefeller 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: Locomotion control with photopigments

Researchers from Göttingen University discover additional function of opsins

Animal photoreceptors capture light with photopigments. Researchers from the University of Göttingen have now discovered that these photopigments fulfill an...

Im Focus: Surveying the Arctic: Tracking down carbon particles

Researchers embark on aerial campaign over Northeast Greenland

On 15 March, the AWI research aeroplane Polar 5 will depart for Greenland. Concentrating on the furthest northeast region of the island, an international team...

Im Focus: Unique Insights into the Antarctic Ice Shelf System

Data collected on ocean-ice interactions in the little-researched regions of the far south

The world’s second-largest ice shelf was the destination for a Polarstern expedition that ended in Punta Arenas, Chile on 14th March 2018. Oceanographers from...

Im Focus: ILA 2018: Laser alternative to hexavalent chromium coating

At the 2018 ILA Berlin Air Show from April 25–29, the Fraunhofer Institute for Laser Technology ILT is showcasing extreme high-speed Laser Material Deposition (EHLA): A video documents how for metal components that are highly loaded, EHLA has already proved itself as an alternative to hard chrome plating, which is now allowed only under special conditions.

When the EU restricted the use of hexavalent chromium compounds to special applications requiring authorization, the move prompted a rethink in the surface...

Im Focus: Radar for navigation support from autonomous flying drones

At the ILA Berlin, hall 4, booth 202, Fraunhofer FHR will present two radar sensors for navigation support of drones. The sensors are valuable components in the implementation of autonomous flying drones: they function as obstacle detectors to prevent collisions. Radar sensors also operate reliably in restricted visibility, e.g. in foggy or dusty conditions. Due to their ability to measure distances with high precision, the radar sensors can also be used as altimeters when other sources of information such as barometers or GPS are not available or cannot operate optimally.

Drones play an increasingly important role in the area of logistics and services. Well-known logistic companies place great hope in these compact, aerial...

All Focus news of the innovation-report >>>



Industry & Economy
Event News

Ultrafast Wireless and Chip Design at the DATE Conference in Dresden

16.03.2018 | Event News

International Tinnitus Conference of the Tinnitus Research Initiative in Regensburg

13.03.2018 | Event News

International Virtual Reality Conference “IEEE VR 2018” comes to Reutlingen, Germany

08.03.2018 | Event News

Latest News

Wandering greenhouse gas

16.03.2018 | Earth Sciences

'Frequency combs' ID chemicals within the mid-infrared spectral region

16.03.2018 | Physics and Astronomy

Biologists unravel another mystery of what makes DNA go 'loopy'

16.03.2018 | Life Sciences

Science & Research
Overview of more VideoLinks >>>