Navigation Links
Gene 'knockout' floors tobacco carcinogen
Date:3/18/2008

In large-scale field trials, scientists from North Carolina State University have shown that silencing a specific gene in burley tobacco plants significantly reduces harmful carcinogens in cured tobacco leaves.

The finding could lead to tobacco products especially smokeless products with reduced amounts of cancer-causing agents.

NC State's Dr. Ralph Dewey, professor of crop science, and Dr. Ramsey Lewis, assistant professor of crop science, teamed with colleagues from the University of Kentucky to knock out a gene known to turn nicotine into nornicotine. Nornicotine is a precursor to the carcinogen N-nitrosonornicotine (NNN). Varying percentages of nicotine are turned into nornicotine while the plant ages; nornicotine converts to NNN as the tobacco is cured, processed and stored.

The field tests in Kentucky, Virginia and North Carolina compared cured burley tobacco plants with the troublesome gene silenced and "control" plant lines with normal levels of gene expression. The researchers found a six-fold decrease in carcinogenic NNN in the genetically modified tobacco plants, as well as a 50 percent overall reduction in the class of harmful compounds called TSNAs, or tobacco-specific nitrosamines. TSNAs are reported to be among the most important tobacco-related compounds implicated in various cancers in laboratory experiments, Lewis said.

The research results were published online in Plant Biotechnology Journal.

Lewis and Dewey stress that the best way for people to avoid the risks associated with tobacco use is to avoid using tobacco products. But their findings show that targeted gene silencing can work as well in the field as it does on the lab bench.

"Creating a tobacco plant with fewer or no harmful compounds may also help with tobacco plants that are being used to create pharmaceuticals or other high-value products," Dewey said.

To get initial lines of plants with the troublesome gene silenced, the NC State researchers used a technique called RNA interference in which genetic engineering was used to introduce a gene that inhibits the demethylase gene function into the tobacco plant.

Dewey and Lewis have since developed tobacco lines with the same effect without using genetic engineering. They randomly inserted chemical changes, or mutations, into the tobacco genome of burley tobacco plants. They then searched for plants in which the nicotine demethylase gene was permanently impaired. The researchers are currently working to transfer this mutation to widely used tobacco varieties.

Dewey and Lewis add that nothing else in the plant changed growth or resistance to insects or disease, for example after they knocked out this specific gene.

While Lewis believes that varieties of burley tobacco with a silenced demethylase gene will exist within the next few years, the NC State researchers say burley tobacco has a number of other targets for their gene silencing method.


'/>"/>

Contact: Dr. Ralph Dewey
ralph_dewey@ncsu.edu
919-515-2705
North Carolina State University
Source:Eurekalert

Related medicine news :

1. Pitt study finds inequality in tobacco advertising
2. Tennessee Faith Leaders Call on Reps. Gordon & Blackburn to Co-sponsor Legislation to Protect Kids from Tobacco
3. OSF HealthCare Achieves Impressive Tobacco Quit Rates with the Free & Clear(R) Quit For Life(TM) Program
4. President Bush Should Protect Kids, Not Big Tobacco By Signing Bill to Increase Cigarette Tax, Fund SCHIP
5. Tobacco-Free Kids Applauds Tyra Banks for Exposing the Ugly Truth About Smoking
6. Congressional Support Grows for FDA Regulation of Tobacco: Bill Now Sponsored by 55 Senators, 200 Representatives
7. Congress Starts Hearings on FDAs Control of Tobacco
8. Presidents Veto of Bill to Increase Cigarette Tax, Fund SCHIP Benefits Big Tobacco at Expense of Americas Kids
9. UGA study: Youth exposed to smokeless tobacco ads despite settlement
10. Big Tobaccos Latest Dirty Trick: Deceiving Oregon Voters
11. Virginia Faith Leaders Call on Senators Webb & Warner to Cosponsor Legislation to Protect Kids from Tobacco
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:2/13/2016)... Angeles, California (PRWEB) , ... February 13, 2016 , ... ... help landing a date for the big day. A great outfit, flawless hair, and ... ashtray, they might as well resign themselves to a night at home with Rover. ...
(Date:2/13/2016)... Viejo, CA (PRWEB) , ... February 13, 2016 , ... ... ember particle overlays to footage all within Final Cut Pro X. Each user can ... control over 3D rotation, angle of view, blur, focus offset, hue, saturation, value, contrast, ...
(Date:2/13/2016)... ... February 13, 2016 , ... Christie Medical ... in-kind gift of a VeinViewer® Vision vein finder for the nursing ... start an IV and draw blood, combining technology with traditional technique. , “VeinViewer ...
(Date:2/13/2016)... ... , ... DDi , a Makro company, makes it ... expertise in eClinical Solutions. DDi has built its solution competency with a unique ... clients. DDi provides smarter technology for Clinical Development, Regulatory and Enterprise domains by ...
(Date:2/12/2016)... ... February 12, 2016 , ... The law firm of Morrow, Morrow, Ryan & ... purpose of these scholarships is to encourage applicants to pursue a degree in their ... these two parishes. , “We have available jobs in St. Landry and Evangeline ...
Breaking Medicine News(10 mins):
(Date:2/11/2016)... 2016  Kindred Biosciences, Inc. (NASDAQ: KIN ), ... lives of pets, today announced the submission to FDA ... Drug Application (NADA) for Zimeta™ (dipyrone injection, KIND-012).  Positive ... Zimeta for the control of pyrexia (fever) in horses ... --> --> The Chemistry, Manufacturing, and ...
(Date:2/11/2016)... , Feb. 11, 2016   Health 2.0 ... of new health technologies, announced today " 10 Year ... in health tech over the past ten years.   ... nearly a decade, Health 2.0 has served as the ... and connected with thousands of technologies, companies, innovators, and ...
(Date:2/11/2016)... 11, 2016  MiMedx Group, Inc. (NASDAQ: MDXG ... membrane and other birth tissues, human skin and bone, ... market advanced products and therapies, announced today that it ... Healthcare Conference in New York , ... Michael J. Senken , Chief Financial Officer and ...
Breaking Medicine Technology: