Featured Research

from universities, journals, and other organizations

Engineering Aluminum-tolerant Crop Plants: Biochemists Devise Method For Bypassing Toxicity Effects

Date:
October 13, 2008
Source:
University of California - Riverside
Summary:
Aluminum toxicity, a global agricultural problem, halts root growth in plants, severely limiting agricultural productivity for more than half of the world's arable land. Now biochemists have determined that it is not aluminum toxicity that is directly responsible for inhibiting plant growth. The researchers identified a factor in plant cells, called AtATR, that functions as a built-in DNA surveillance system for alerting the plant of damage from excess aluminum and shutting down growth.

Paul Larsen, an associate professor of biochemistry at UC Riverside, examines an Arabidopsis plant.
Credit: UCR Strategic Communications

Aluminum toxicity, a global agricultural problem, halts root growth in plants, severely limiting agricultural productivity for more than half of the world's arable land.

For many years, scientists have puzzled over how toxic levels of aluminum damage the growing root. The popular understanding is that aluminum binds to several targets in the root system, blocking cell division, damaging DNA, and ultimately interrupting plant growth.

Now, working on the model plant Arabidopsis, a team of UC Riverside biochemists has determined that it is not aluminum toxicity that is directly responsible for inhibiting plant growth. The researchers identified a factor in plant cells, called AtATR, that functions as a built-in DNA surveillance system for alerting the plant of damage from excess aluminum and shutting down growth.

The researchers' experiments showed that AtATR can be manipulated to greatly enhance aluminum tolerance, resulting in plants whose roots can grow normally in soils that contain toxic levels of aluminum.

Study results appear in the Oct. 14 issue of Current Biology.

"Plants actively monitor aluminum-dependent damage through AtATR," said Paul Larsen, an associate professor of biochemistry and the lead author of the study. "But by breaking this assessment mechanism in a plant growing in soil with high aluminum content, we were able to stimulate plant growth again because the plant was no longer able to sense the damage aluminum caused. In other words, by bypassing this growth checkpoint, plants are not able to sense the effects of aluminum; they continue to grow even in an aluminum-toxic environment that is highly inhibitory to a normal Arabidopsis plant."

The research, which gives scientists new insights into how aluminum tolerance works in plants, offers a new strategy for engineering crop plants that can tolerate growth in aluminum-toxic environments, increasing crop production in areas that otherwise could not sustain agriculture.

"Dr. Larsen's work is a significant breakthrough in our understanding of how aluminum toxicity inhibits root growth," said Leon Kochian, a professor of plant biology at Cornell University, who was not involved in the research. "What he has shown, using an elegant combination of genetics, molecular biology and physiology, is that aluminum causes DNA damage in the growing root tip. The cells of this region have a mechanism to monitor this damage and shut down cell division and thus, root growth."

Larsen explained that a root tip has a "quiescent center" that houses stem cells – master cells, maintained throughout the life of the root, that develop into cell types and tissues. Aluminum toxicity results in the loss of these stem cells, and consequently cell division, bringing growth to a halt.

"Knocking off AtATR's functioning maintains the quiescent center," said Larsen, who joined UCR's Department of Biochemistry in 2000. "In our study, we broke AtATR throughout the plant. But if we can break this factor only in the root tip, the plant will not sense aluminum's damage to the root. The root then continues to grow and we regain productivity."

The researchers' experiments involved introducing random mutations throughout the genome of Arabidopsis and screening for those roots that can grow in the presence of high levels of aluminum.

A silvery-white metal, aluminum is the most abundant metallic element in the Earth's crust. Never found in the metallic form in nature, it occurs instead in compounds.

Next, Larsen's lab will work on identifying other factors in plants that detect DNA damage. His lab also plans to induce the AtATR mutation into crop plants such as tomato and corn to increase their aluminum tolerance.

Larsen was joined in the research by Megan A. Rounds, his graduate student. Grants from the National Science Foundation and the United States Department of Agriculture funded the five-year study.

UCR's Office of Technology Commercialization has applied for a patent on Larsen's discovery, and is looking for commercial partners interested in developing the technology.


Story Source:

The above story is based on materials provided by University of California - Riverside. Note: Materials may be edited for content and length.


Cite This Page:

University of California - Riverside. "Engineering Aluminum-tolerant Crop Plants: Biochemists Devise Method For Bypassing Toxicity Effects." ScienceDaily. ScienceDaily, 13 October 2008. <www.sciencedaily.com/releases/2008/10/081002171906.htm>.
University of California - Riverside. (2008, October 13). Engineering Aluminum-tolerant Crop Plants: Biochemists Devise Method For Bypassing Toxicity Effects. ScienceDaily. Retrieved July 23, 2014 from www.sciencedaily.com/releases/2008/10/081002171906.htm
University of California - Riverside. "Engineering Aluminum-tolerant Crop Plants: Biochemists Devise Method For Bypassing Toxicity Effects." ScienceDaily. www.sciencedaily.com/releases/2008/10/081002171906.htm (accessed July 23, 2014).

Share This




More Plants & Animals News

Wednesday, July 23, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Michigan Plant's Goal: Flower and Die

Michigan Plant's Goal: Flower and Die

AP (July 22, 2014) An 80-year-old agave plant, which is blooming for the first and only time at a University of Michigan conservatory, will die when it's done (July 22) Video provided by AP
Powered by NewsLook.com
San Diego Zoo Welcomes New, Rare Rhino Calf

San Diego Zoo Welcomes New, Rare Rhino Calf

Reuters - US Online Video (July 21, 2014) An endangered black rhino baby is the newest resident at the San Diego Zoo. Sasha Salama reports. Video provided by Reuters
Powered by NewsLook.com
Shark Sightings a Big Catch for Cape Tourism

Shark Sightings a Big Catch for Cape Tourism

AP (July 21, 2014) A rise in shark sightings along the shores of Chatham, Massachusetts is driving a surge of eager vacationers to the beach town looking to catch a glimpse of a great white. (July 21) Video provided by AP
Powered by NewsLook.com
$23.6 Billion Awarded To Widow In Smoking Lawsuit

$23.6 Billion Awarded To Widow In Smoking Lawsuit

Newsy (July 20, 2014) Cynthia Robinson claims R.J. Reynolds Tobacco Company hid the health and addiction risks of its products, leading to the death of her husband in 1996. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins