Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Researchers ID chlorophyll-regulating gene

24.09.2004


Researchers at the University of California, Berkeley, have identified a critical gene for plants that start their lives as seeds buried in soil. They say the burial of seeds was an adaptation that likely helped plants spread from humid, wet climates to drier, hostile environments.



In a study published in the Sept. 24 issue of the journal Science, the researchers describe how a gene called phytochrome-interacting factor 1, or PIF1, affects the production of protochlorophyll, a precursor of the chlorophyll used by plants to convert the sun’s energy into food during photosynthesis.

While a seed germinates under soil, in the dark, it is producing a controlled amount of protochlorophyll in preparation for its debut above ground. Much like a baby takes his or her first breath of air after emerging from the womb, seedlings must quickly convert protochlorophyll into chlorophyll once they are exposed to light for the first time. "It’s a delicate balancing act," said Peter Quail, professor of plant and microbial biology at UC Berkeley’s College of Natural Resources and principal investigator of the study. "The young plant needs some protochlorophyll to get the ball rolling in photosynthesis. But if the plant accumulates too much of the compound, it leads to photo-oxidative stress, which is seen as bleaching on the leaves. The overproduction of protochlorophyll is like a ticking time bomb that is set off by the sun."


Quail is also research director of the Plant Gene Expression Center, a joint research center of the Agricultural Research Service of the U.S. Department of Agriculture and the University of California. The researchers targeted the PIF1 gene because it binds to phytochrome, a protein that is triggered by light and that controls a plant’s growth and development. The researchers disabled the PIF1 gene in the species Arabidopsis thaliana, a mustard plant, and compared the mutant seedlings with a control group of normal plants.

They grew the seedlings in the dark to mimic conditions beneath the soil, bringing groups out into the light at different time points throughout a six-day period. In nature, seeds are typically buried under 2 to 10 millimeters of soil, taking anywhere from two to seven days to germinate and break through the soil surface. "We found that mutated plants had twice the levels of protochlorophyll than normal, wild-type plants, suggesting that phytochrome acts as a negative regulator for protochlorophyll," said lead author Enamul Huq, who conducted the study while he was a post-doctoral researcher at UC Berkeley’s Department of Plant and Microbial Biology. "We also saw that the longer the seedlings were grown in the dark, the more likely they would die when they were exposed to light."

The mutated seedlings failed to switch off production of protochlorophyll throughout the germination period, so the longer the seedlings stayed in the dark, the more toxic the levels became. Huq, now an assistant professor of molecular cell and developmental biology at the University of Texas at Austin, pointed out that it is an "unbound" form of protochlorophyll that is toxic. Normal plants, he said, produce enough of an enzyme, called protochlorophyllide oxidoreductase, to bind with typical levels of protochlorophyll. But not enough of the enzyme is produced to handle the overabundance of unbound protochlorophyll churned out by the mutant seedlings.

The researchers say the ability of plants to precisely regulate production of protochlorophyll was probably an evolutionary development designed to ensure seed survival among higher plants. Primitive plants, such as mosses and some species of fern, thrive in moist, humid environments where their spores can stay safely above the soil surface. But all higher plants - from grasses to trees to agricultural crops such as wheat and corn - must have the ability to transition from the darkness of an underground environment to life above ground. "The development of seed burial in plants provided a long-term survival benefit through protection from predators and hostile surface conditions," said Quail. "The true test of our hypothesis would be to verify whether primitive plants have the PIF1 gene, and whether the gene is functional."

The finding may also have implications for agricultural biotechnology, allowing researchers to manipulate the gene to improve the efficiency with which plants carry on photosynthesis.

Sarah Yang | EurekAlert!
Further information:
http://www.berkeley.edu

More articles from Life Sciences:

nachricht Mass spectrometry sheds new light on thallium poisoning cold case
14.12.2018 | University of Maryland

nachricht Protein involved in nematode stress response identified
14.12.2018 | University of Illinois College of Agricultural, Consumer and Environmental Sciences

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Data use draining your battery? Tiny device to speed up memory while also saving power

The more objects we make "smart," from watches to entire buildings, the greater the need for these devices to store and retrieve massive amounts of data quickly without consuming too much power.

Millions of new memory cells could be part of a computer chip and provide that speed and energy savings, thanks to the discovery of a previously unobserved...

Im Focus: An energy-efficient way to stay warm: Sew high-tech heating patches to your clothes

Personal patches could reduce energy waste in buildings, Rutgers-led study says

What if, instead of turning up the thermostat, you could warm up with high-tech, flexible patches sewn into your clothes - while significantly reducing your...

Im Focus: Lethal combination: Drug cocktail turns off the juice to cancer cells

A widely used diabetes medication combined with an antihypertensive drug specifically inhibits tumor growth – this was discovered by researchers from the University of Basel’s Biozentrum two years ago. In a follow-up study, recently published in “Cell Reports”, the scientists report that this drug cocktail induces cancer cell death by switching off their energy supply.

The widely used anti-diabetes drug metformin not only reduces blood sugar but also has an anti-cancer effect. However, the metformin dose commonly used in the...

Im Focus: New Foldable Drone Flies through Narrow Holes in Rescue Missions

A research team from the University of Zurich has developed a new drone that can retract its propeller arms in flight and make itself small to fit through narrow gaps and holes. This is particularly useful when searching for victims of natural disasters.

Inspecting a damaged building after an earthquake or during a fire is exactly the kind of job that human rescuers would like drones to do for them. A flying...

Im Focus: Topological material switched off and on for the first time

Key advance for future topological transistors

Over the last decade, there has been much excitement about the discovery, recognised by the Nobel Prize in Physics only two years ago, that there are two types...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

ICTM Conference 2019: Digitization emerges as an engineering trend for turbomachinery construction

12.12.2018 | Event News

New Plastics Economy Investor Forum - Meeting Point for Innovations

10.12.2018 | Event News

EGU 2019 meeting: Media registration now open

06.12.2018 | Event News

 
Latest News

Data use draining your battery? Tiny device to speed up memory while also saving power

14.12.2018 | Power and Electrical Engineering

Tangled magnetic fields power cosmic particle accelerators

14.12.2018 | Physics and Astronomy

In search of missing worlds, Hubble finds a fast evaporating exoplanet

14.12.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>