Navigation Links
Defining gene's role may lead to prevention of dangerous corn toxin
Date:3/25/2008

WEST LAFAYETTE, Ind. - Discovery that a specific gene is integral to both fungal invasion of corn and development of a potentially deadly toxin in the kernels may lead to ways to control the pathogen and the poison.

Purdue University researchers evaluated the fungal gene ZFR1 and found that it is vital to the process of the fungus growing on corn kernels. Production of the toxin decreased when the scientists disabled the gene.

At certain levels, the toxin can cause illness in humans and most domestic livestock. Horses and pigs are at particular risk and can develop fatal diseases by ingesting feed containing one of a group of toxins called fumonisins (few-mahn-ah-sins). About $40 million of the U.S. corn crop is lost annually due to presence of these toxins, according to experts.

"Our main research question has been what triggers toxin production when the fungus attacks the corn kernel; it appears that kernel starch plays an important role," said Charles Woloshuk, a Purdue plant pathologist. "When ZFR1 is deleted, the resulting mutant fungus has a problem transporting sugars that are produced from the degradation of kernel starch."

The resulting sugars must be transported to cells as fuel for other biochemical processes.

"The pathogen - the fungus Fusarium verticillioides - has a number of putative sugar transporter genes that are expressed during its growth on kernels and toxin production," Woloshuk said. "Disruption of ZFR1 also affects expression of the sugar transporter genes."

Woloshuk and his colleague, Bert Bluhm, now at the University of Arkansas, report in the current issue of Molecular Plant Pathology that when the gene ZFR1 is turned off, it reduces manifestation of genes involved in production of the most prevalent and dangerous fumonisin, FB1.

The researchers studied ZFR1 regulation of fungal growth and toxin production in the starch-rich areas of corn kernels and the conversion of starch to glucose, glucose recognition and the expression of sugar transporter genes. From this information, Woloshuk and his team identified a specific sugar transporter, FST1 (fusarium sugar transporter1), that is necessary for FB1 production.

Although FST1 is required for FB1 production, it is not involved with the fungus infecting corn kernels. This led the scientists to hypothesize that FST1 acts as a molecular sensor necessary for toxin production.

Kernels with lower starch content, most notably immature kernels, don't support toxin production, Woloshuk said. This is evidence that the kernel makeup dictates how this pathogen controls toxin production.

Corn and fungal growth were unaffected when the sugar transporter gene was disrupted, but toxin production on the kernels was cut by about 82 percent, Woloshuk said.

When fusarium invades corn in the field, it causes an ear rot disease. Even knowing that ear rot is present doesn't help identify corn containing toxin because obvious signs of the fungus don't correlate with presence of toxins. The only way to confirm toxin is present is to test for it. Testing is so expensive, however, that it usually isn't done unless the disease is highly evident.

Weather and insect damage impact development of a variety of fungi and toxins and also influence the level of poisons that are present. Toxins are more likely to develop in corn when hot, dry weather is followed by highly humid or wet weather.

The group of toxins associated with varieties of fusarium species are known as mycotoxins. Some clinical evidence links these toxins with certain human cancers.

Grains grown for cereal and feeds are susceptible to one or more of the fusarium fungi species. Wheat and barley attacked by one of the species closely related to Fusarium verticillioides can develop head blight and accumulate mycotoxins, causing billions of dollars in crop losses worldwide.

Further study is needed because the researchers still don't know what triggers the biochemical process that regulates ZFR1 and consequently leads to toxin production, Woloshuk said. The scientists also are investigating the sugar transporter genes to discover if they have other roles in the fungus and what molecular interactions between the fungus and the plant allow infection and toxin production.

"We're closer to finding some of the triggers in corn that assist the fungus in toxin production," Woloshuk said.


'/>"/>

Contact: Susan A. Steeves
ssteeves@purdue.edu
765-496-7481
Purdue University
Source:Eurekalert  

Related biology news :

1. Gene regulation, not just genes, is what sets humans apart
2. Interaction of just 2 genes governs coloration patterns in mice
3. Muscle mass: Scientists identify novel mode of transcriptional regulation during myogenesis
4. Study finds blocking angiogenesis signaling from inside cell may lead to serious health problems
5. Smoking turns on genes -- permanently
6. Genes, Environment and Health Initiative invests in genetic studies, environmental monitoring
7. Hebrew SeniorLife researchers search for aging, osteoporosis genes
8. UT Southwestern researchers identify hundreds of genes controlling female fertility
9. Genes and environment grant funds close look at nature-nurture overlap in common diseases
10. Jumping genes could make for safer gene delivery system
11. Genes from the father facilitate the formation of new species
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
Defining gene's role may lead to prevention of dangerous corn toxin
(Date:1/11/2017)... 11, 2017  Michael Johnson, co-founder of Visikol Inc. a company ... has been named to the elite "Forbes 30 Under 30" list ... 600 people in 20 fields nationwide to be recognized as a ... applicants were selected. ... He is currently a PhD candidate at Rutgers University. ...
(Date:1/6/2017)... 5, 2017  Delta ID Inc., a leader in ... for automotive at CES® 2017. Delta ID has collaborated ... demonstrate the use of iris scanning as a secure, ... driver in a car, and as a way to ... Delta ID and Gentex will demonstrate (booth ...
(Date:1/3/2017)... 2017 Onitor, provider of digital health technology ... an innovative biometric data-driven program designed to aid weight ... the 2017 Consumer Electronics Show (CES) in ... U.S., the World Health Organization (WHO), have identified lifestyle ... who are overweight or obese. WHO also states that ...
Breaking Biology News(10 mins):
(Date:1/19/2017)... ... January 19, 2017 , ... ... the full spectrum of drug and device development, and Prism Clinical Research ... and clinicians, today announced Verified Clinical Trials (VCT) has been selected ...
(Date:1/19/2017)... BETHESDA, Md. , Jan. 18, 2017  Northwest ... company developing DCVax® personalized immune therapies for operable and ... Marnix Bosch , Chief Technical Officer of NW Bio, ... Thursday, January 19, 2017, at the Hyatt Regency Hotel ... Dr. Bosch will chair the session entitled "New Therapeutic ...
(Date:1/19/2017)... Jan. 18, 2017 BD (Becton, Dickinson and Company) (NYSE: ... that it will host a live webcast of its Annual Meeting ... The webcast can be accessed from the BD ... through Tuesday, January 31, 2017. ... About BD BD is a global medical ...
(Date:1/18/2017)... According to a new market research report "In situ Hybridization Market by Technique ... Diagnostic Laboratories, Academic and Research Institutions) - Global Forecast to 2021" published by ... USD 557.1 Million in 2016, growing at a CAGR of 5.8%. ... ... MarketsandMarkets Logo ...
Breaking Biology Technology: