PRESS-NEWS.org - Press Release Distribution
PRESS RELEASES DISTRIBUTION

Switching on a dime: How plants function in shade and light

Switching on a dime: How plants function in shade and light
2014-11-13
(Press-News.org) Stanford, CA--Photosynthesis is the process by which plants convert energy from the sunlight into chemical energy in the form of sugars. These sugars are used by plants to grow and function, as well as food for animals and humans that eat them.

Plants grow in environments where the availability of light fluctuates quickly and drastically, for example from the shade of clouds passing overhead or of leaves on overhanging trees blowing in the wind. Plants thus have to rapidly adjust photosynthesis to maximize energy capture while preventing excess energy from causing damage. So how do plants prevent these changes in light intensity from affecting their ability to harvest the energy they need to survive? The response has to be extremely swift. A team of researchers led by Carnegie's Ute Armbruster and Martin Jonikas revealed a mechanism by which plants maintain high photosynthetic efficiency in fluctuating light. Their work is published in Nature Communications.

The question of how photosynthetic efficiency is maintained affects plants on which humans depend, including crops and even forests, so answering this question has practical implications for improving agricultural productivity.

The team, which also includes Carnegie's Ari Kornfeld and Joseph Berry, discovered that a protein, called KEA3, is crucial for immediate adjustment of photosynthetic efficiency in fluctuating light conditions.

Photosynthesis takes place in stages. The first stage absorbs light in the form of photons and uses it to produce energy storage molecules, which are then used to power the second stage, which fixes carbon from the air into carbon-based sugars, such as sucrose and starch.

KEA3 is concerned with the first stage.

Under full sunlight, the energy from excess absorbed photons is intentionally dissipated by the plant as heat. But if the incident light is blocked by a cloud, the plant must switch from dissipating excess photons as heat to harvesting as many photons as possible. Advanced analytical techniques demonstrated that KEA3 acts to accelerate the switch from the full-sunlight-adapted mode to the shade-adapted mode. This rapid response to light intensity makes the first stage of photosynthesis more efficient.

Mutant plants without functioning KEA3 transporters lost a great deal of harvested light energy as heat during a transition to low light, further underpinning their finding.

"Our discovery of this built-in machinery for responding to light conditions makes KEA3 a new target for those interested in improving crop productivity, as well as for advancing basic knowledge of photosynthetic biochemistry," Jonikas said.

INFORMATION:

The paper's other co-authors are David Kramer and L. Ruby Carrillo of Michigan State University, Kees Venema of the Consejo Superior de Investigaciones Científicas in Spain, and Peter Jahns and Lazar Pavlovic of Heinrich-Heine-Universität in Germany. This project was funded by the Carnegie Institution for Science, by ERDF-cofinanced grants from the Ministry of Economy and Competitiveness and Junta de Andalucia, the Natural Sciences and Engineering Research Council of Canada PGS-D3 scholarship, and Deutsche Forschungsgemeinschaft grants.

The Carnegie Institution for Science is a private, nonprofit organization headquartered in Washington, D.C., with six research departments throughout the U.S. Since its founding in 1902, the Carnegie Institution has been a pioneering force in basic scientific research. Carnegie scientists are leaders in plant biology, developmental biology, astronomy, materials science, global ecology, and Earth and planetary science.


[Attachments] See images for this press release:
Switching on a dime: How plants function in shade and light Switching on a dime: How plants function in shade and light 2

ELSE PRESS RELEASES FROM THIS DATE:

Moms with rheumatoid arthritis more likely to give birth prematurely

2014-11-13
Researchers from Denmark and the U.S. report that babies of women with rheumatoid arthritis (RA) or pre-clinical RA--the period prior to symptoms--are 1.5 times more likely to be born prematurely in Denmark. Findings published in Arthritis & Rheumatology, a journal of the American College of Rheumatology (ACR), indicate that body measurements of the baby at birth were only slightly lower in children exposed to maternal or preclinical RA compared to those with no exposure to the disease. Paternal RA was not found to impact fetal growth or preterm birth risk. Roughly one ...

Did men evolve navigation skills to find mates?

Did men evolve navigation skills to find mates?
2014-11-13
SALT LAKE CITY, Nov. 13, 2014 - A University of Utah study of two African tribes found evidence that men evolved better navigation ability than women because men with better spatial skills - the ability to mentally manipulate objects - can roam farther and have children with more mates. By testing and interviewing dozens of members of the Twe and Tjimba tribes in northwest Namibia, the anthropologists showed that men who did better on a spatial task not only traveled farther than other men but also had children with more women, according to the study published this week ...

Pre-pregnancy body weight affects early development of human embryos

2014-11-13
New research indicates that the embryos of women who are overweight or obese at the time they conceive display distinct differences in early development compared to embryos from women of a healthy weight. The results of the study, published today in the journal Human Reproduction, provide strong evidence for a direct link between what mothers eat and the ability of their fertilised eggs to divide and grow. The researchers claim this could potentially have long-term health implications for any children born from these embryos. The four key findings of the study, which ...

Mongoose sentinels respond flexibly to threats

2014-11-13
Just as soldiers on sentry duty constantly adjust their behaviour to match the current threat level, dwarf mongoose sentinels exhibit flexible decision-making in relation to predation risk, new research from the University of Bristol has shown. Biologists Julie Kern and Dr Andy Radford found that decisions about when to go on duty, what position to adopt and how long to remain on post were all affected by information about the likelihood of danger. Sentinels altered their behaviour depending on both environmental conditions, such as wind speed and social signals, such ...

Do homing pigeons navigate with gyroscope in brain?

2014-11-13
Human communication has long been associated with an unlikely companion, the homing pigeon; but how these pigeons find their way home is still largely a mystery. 'There is widespread agreement that pigeons are able to determine and maintain flight (compass) directions based on solar and magnetic cues,' says Hans-Peter Lipp from the University of Zurich, Switzerland, and Kwazulu-Natal University, South Africa. However, another piece of the puzzle - how the bird determines its position, known as the map sense - was unclear. Dissatisfied with the current theories - that pigeons ...

Climate change puts coastal crabs in survival mode, study finds

2014-11-13
SAN FRANCISCO, Nov. 12, 2014 -- Porcelain crabs can adapt to a warming climate but will not have energy for much else beyond basic survival, according to new research published today from San Francisco State University. The findings have grim long-term implications for intertidal zone crabs as well as the myriad species that depend on them, and could be an indicator of how other intertidal organisms may respond to a rapidly changing climate. The study is detailed in an article published in the Journal of Experimental Biology and is the first to explore intertidal zone ...

Prostate cancer researchers develop personalized genetic test to predict recurrence risk

2014-11-13
(TORONTO, Canada - Nov. 13, 2014) - Prostate cancer researchers have developed a genetic test to identify which men are at highest risk for their prostate cancer to come back after localized treatment with surgery or radiotherapy. The findings are published online today in Lancet Oncology. Study co-leads Dr. Robert Bristow, a clinician-scientist at Princess Margaret Cancer Centre, and Dr. Paul Boutros, an investigator at the Ontario Institute for Cancer Research, report that the gene test provides a much-needed quick and accurate tool to determine with greater precision ...

Errors in single gene may protect against heart disease

2014-11-13
Rare mutations that shut down a single gene are linked to lower cholesterol levels and a 50 percent reduction in the risk of heart attack, according to new research from Washington University School of Medicine in St. Louis, the Broad Institute at Massachusetts Institute of Technology and Harvard, and other institutions. The gene, called NPC1L1, is of interest because it is the target of the drug ezetimibe, often prescribed to lower cholesterol. The study appears Nov. 12 in The New England Journal of Medicine. Everyone inherits two copies of most genes -- one copy ...

Picture emerges of how kids get head injuries

2014-11-13
A study in which more than 43,000 children were evaluated for head trauma offers an unprecedented picture of how children most frequently suffer head injuries, report physicians at Washington University School of Medicine in St. Louis and the University of California, Davis, School of Medicine. The findings also indicate how often such incidents result in significant brain injuries, computerized tomography (CT) scans to assess head injuries, and neurosurgery to treat them. In children ages 12 and younger, falls were the most common cause of head injuries. In children ...

Experts address challenges of delivering critical care in resource-poor countries

2014-11-13
Philadelphia, PA, November 12, 2014 - Critical care is defined by life-threatening conditions, which require close evaluation, monitoring, and treatment by appropriately trained health professionals. Cardiovascular care bears these same requirements. In fact, cardiovascular disease will soon surpass even human immunodeficiency virus (HIV) as the leading cause of mortality in Sub-Saharan Africa. In the latest issue of Global Heart, researchers discuss the challenges of delivering critical care in resource-limited countries. According to Guest Editors Vanessa Kerry, MD, ...

LAST 30 PRESS RELEASES:

Are lifetimes of big appliances really shrinking?

Pink skies

Monkeys are world’s best yodellers - new research

Key differences between visual- and memory-led Alzheimer’s discovered

% weight loss targets in obesity management – is this the wrong objective?

An app can change how you see yourself at work

NYC speed cameras take six months to change driver behavior, effects vary by neighborhood, new study reveals

New research shows that propaganda is on the rise in China

Even the richest Americans face shorter lifespans than their European counterparts, study finds

Novel genes linked to rare childhood diarrhea

New computer model reveals how Bronze Age Scandinavians could have crossed the sea

Novel point-of-care technology delivers accurate HIV results in minutes

Researchers reveal key brain differences to explain why Ritalin helps improve focus in some more than others

Study finds nearly five-fold increase in hospitalizations for common cause of stroke

Study reveals how alcohol abuse damages cognition

Medicinal cannabis is linked to long-term benefits in health-related quality of life

Microplastics detected in cat placentas and fetuses during early pregnancy

Ancient amphibians as big as alligators died in mass mortality event in Triassic Wyoming

Scientists uncover the first clear evidence of air sacs in the fossilized bones of alvarezsaurian dinosaurs: the "hollow bones" which help modern day birds to fly

Alcohol makes male flies sexy

TB patients globally often incur "catastrophic costs" of up to $11,329 USD, despite many countries offering free treatment, with predominant drivers of cost being hospitalization and loss of income

Study links teen girls’ screen time to sleep disruptions and depression

Scientists unveil starfish-inspired wearable tech for heart monitoring

Footprints reveal prehistoric Scottish lagoons were stomping grounds for giant Jurassic dinosaurs

AI effectively predicts dementia risk in American Indian/Alaska Native elders

First guideline on newborn screening for cystic fibrosis calls for changes in practice to improve outcomes

Existing international law can help secure peace and security in outer space, study shows

Pinning down the process of West Nile virus transmission

UTA-backed research tackles health challenges across ages

In pancreatic cancer, a race against time

[Press-News.org] Switching on a dime: How plants function in shade and light