MU researchers make discovery in molecular mechanics of phototropism

July 05, 2007

COLUMBIA, Mo. - In a paper published in the Journal of Biological Chemistry, scientists at the University of Missouri-Columbia reported molecular-level discoveries about the mechanisms of phototropism, the directional growth of plants toward or away from light.

Phototropism is initiated when photoreceptors in a plant sense directional blue light. Understanding phototropism is important because it could lead to crop improvement, said Mannie Liscum, professor in the Division of Biological Sciences in MU's College of Arts and Science and Christopher S. Bond Life Sciences Center.

"By understanding how phototropism works at a molecular level, we can work toward engineering plants that produce more biomass or have increased drought tolerance, among other things. For example, we could use this information to optimize plants' ability to capture light for photosynthesis, which would result in more energy capture and thus growth, or potentially agronomically useful biomass," Liscum said.

Liscum and doctoral student Ullas Pedmale studied the regulation of phototropic signaling in Arabidopsis thaliana, a weedy flowering plant commonly used as a model in laboratory studies. Focusing on non-phototropic hypocotyls 3 (NPH3), a protein known to be essential for phototropic responses, they examined its phosphorylation, the addition or removal of a phosphate group to the protein molecule. Using a series of pharmacological treatments and immunoblot assays, the team discovered that NPH3 was a phosphorylated protein - a protein with a phosphate group attached - in seedlings grown in the darkness. When the seedlings were exposed to light, they became dephosphorylated, or lost their phosphate group.

These results suggest that the absorption of light by phot1, the dominant receptor controlling phototropism, leads to NPH3's loss of a phosphate group, allowing further progression of phototropic signaling.

"We found that exposure to directional blue light stimulated NPH3's dephosphorylation," Liscum said. "NPH3 exists as a phosphorylated protein in darkness and is rapidly dephosphorylated by a yet unidentified protein phosphatase in response to phot1 photoactivation by blue light."

Liscum and Pedmale now plan to study which amino acids on NPH3 are reversibly phosporylated and how NPH3 is involved in regulating other processes within plants.
-end-


University of Missouri-Columbia

Related Biomass Articles from Brightsurf:

Bound for the EU, American-made biomass checks the right boxes
A first-of-its-kind study published in the journal Scientific Reports finds that wood produced in the southeastern United States for the EU's renewable energy needs has a net positive effect on US forests--but that future industry expansion could warrant more research.

The highest heat-resistant plastic ever is developed from biomass
The use of biomass-derived plastics is one of the prime concerns to establish a sustainable society, which is incorporated as one of the Sustainable Development Goals.

Laser technology measures biomass in world's largest trees
Laser technology has been used to measure the volume and biomass of giant Californian redwood trees for the first time, records a new study by UCL researchers.

Inducing plasma in biomass could make biogas easier to produce
Producing biogas from the bacterial breakdown of biomass presents options for a greener energy future, but the complex composition of biomass comes with challenges.

Microbes working together multiply biomass conversion possibilities
Non-edible plants are a promising alternative to crude oil, but their heterogenous composition can be a challenge to producing high yields of useful products.

Evergreen idea turns biomass DNA into degradable materials
A Cornell-led collaboration is turning DNA from organic matter -- such as onions, fish and algae -- into biodegradable gels and plastics.

Upgrading biomass with selective surface-modified catalysts
Loading single platinum atoms on titanium dioxide promotes the conversion of a plant derivative into a potential biofuel.

A novel biofuel system for hydrogen production from biomass
A recent study, affiliated with South Korea's Ulsan National Institute of Science and Technology (UNIST) has presented a new biofuel system that uses lignin found in biomass for the production of hydrogen.

Biomass fuels can significantly mitigate global warming
'Every crop we tested had a very significant mitigation capacity despite being grown on very different soils and under natural climate variability,' says Dr.

Traditional biomass stoves shown to cause lung inflammation
Traditional stoves that burn biomass materials and are not properly ventilated, which are widely used in developing nations where cooking is done indoors, have been shown to significantly increase indoor levels of harmful PM2.5 (miniscule atmospheric particulates) and carbon monoxide (CO) and to stimulate biological processes that cause lung inflammation and may lead to chronic obstructive pulmonary disease (COPD), according to new research published online in the Annals of the American Thoracic Society.

Read More: Biomass News and Biomass Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.