Featured Research

from universities, journals, and other organizations

Moving Gene In Plant Results In Increased Production Of Amino Acid

Date:
October 3, 2001
Source:
University Of Illinois At Urbana-Champaign
Summary:
By placing a nuclear gene in another location – its original home in a plant – researchers have successfully enhanced the production of an essential amino acid.

CHAMPAIGN, Ill. — By placing a nuclear gene in another location – its original home in a plant – researchers have successfully enhanced the production of an essential amino acid.

The work, which was detailed in the September issue of Plant Physiology, suggests that alterations of biosynthetic pathways could guide plants to produce more of a desired dietary component. In this case, tobacco produced 10 times its usual amount of tryptophan – an amino acid often in short supply in the human diet and vital for the production of serotonin in the brain.

Scientists inserted the gene, known to produce the control enzyme involved in tryptophan production, into the chloroplast genome. Chloroplasts are the chlorophyll containing plastids where photosynthesis occurs. The approach essentially is a reversal of evolution. “The biosynthesis of tryptophan and other essential amino acids occurs in these plastids,” said Archie R. Portis Jr., a University of Illinois crop scientist and researcher in the USDA-Agricultural Research Service Photosynthesis Research Unit at the UI. “However, the genes encoding these enzymes are located in the nucleus and the proteins are imported into the plastids.”

Plastids in today’s plants are believed to have evolved some 2 billion years ago from a unicellular, photosynthetic cyanobacteria containing its own set of genes that was engulfed by

non-photosynthetic cells. “Most of the genes originally located in these early plastids moved to the nucleus,” Portis said. “It is likely that those required for tryptophan biosynthesis were among these.”

The gene the researchers inserted had been isolated previously from a tobacco suspension culture that had been selected for resistance to an inhibitor of tryptophan biosynthesis. That work was done in the laboratory of co-author Jack M. Widholm, a UI professor of crop sciences.

The genetically transformed tobacco plants appeared normal, but they contained a four-fold increase of anthranilate synthase, the control enzyme of tryptophan biosynthesis. The leaves, in turn, had a 10-fold increase in tryptophan compared to non-altered plants.

“The work demonstrates the feasibility of modifying the biosynthetic pathways of important metabolites through transformation of the DNA located in the plastids and relocating native genes in the nucleus,” Portis said. “Plastid transformation is advantageous over nuclear DNA modifications, because it generally allows higher expression of the desired enzymes and restricts unwanted gene movement via pollen, which in most plants does not contain any plastid DNA.”

The technology provides another tool, besides nuclear transformation, for improving yield and value. It could also be used to engineer plants to produce pharmaceuticals such as edible vaccines.

Other co-authors with Portis and Widholm were UI crop scientists Xing-Hai Zhang and Jeffery E. Brotherton. Zhang also is with the USDA-ARS. The Illinois Soybean Program Operating Board, the Illinois Agricultural Experiment Station and the U.S. Department of Agriculture funded the research.


Story Source:

The above story is based on materials provided by University Of Illinois At Urbana-Champaign. Note: Materials may be edited for content and length.


Cite This Page:

University Of Illinois At Urbana-Champaign. "Moving Gene In Plant Results In Increased Production Of Amino Acid." ScienceDaily. ScienceDaily, 3 October 2001. <www.sciencedaily.com/releases/2001/10/011003063842.htm>.
University Of Illinois At Urbana-Champaign. (2001, October 3). Moving Gene In Plant Results In Increased Production Of Amino Acid. ScienceDaily. Retrieved July 29, 2014 from www.sciencedaily.com/releases/2001/10/011003063842.htm
University Of Illinois At Urbana-Champaign. "Moving Gene In Plant Results In Increased Production Of Amino Acid." ScienceDaily. www.sciencedaily.com/releases/2001/10/011003063842.htm (accessed July 29, 2014).

Share This




More Plants & Animals News

Tuesday, July 29, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Deadly Ebola Virus Threatens West Africa

Deadly Ebola Virus Threatens West Africa

AP (July 28, 2014) West African nations and international health organizations are working to contain the largest Ebola outbreak in history. It's one of the deadliest diseases known to man, but the CDC says it's unlikely to spread in the U.S. (July 28) Video provided by AP
Powered by NewsLook.com
Traditional African Dishes Teach Healthy Eating

Traditional African Dishes Teach Healthy Eating

AP (July 28, 2014) Classes are being offered nationwide to encourage African Americans to learn about cooking fresh foods based on traditional African cuisine. The program is trying to combat obesity, heart disease and other ailments often linked to diet. (July 28) Video provided by AP
Powered by NewsLook.com
Asteroid's Timing Was 'Colossal Bad Luck' For The Dinosaurs

Asteroid's Timing Was 'Colossal Bad Luck' For The Dinosaurs

Newsy (July 28, 2014) The asteroid that killed the dinosaurs struck at the worst time for them. A new study says that if it hit earlier or later, they might've survived. Video provided by Newsy
Powered by NewsLook.com
Raw: Sea Turtle Hatchlings Emerge from Nest

Raw: Sea Turtle Hatchlings Emerge from Nest

AP (July 27, 2014) A live-streaming webcam catches loggerhead sea turtle hatchlings emerging from a nest in the Florida Keys. (July 27) Video provided by AP
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