GM safety debate may have new twist

Oct 28, 2010
GM safety debate may have new twist
In planta transformation. Image: By Kirsty Foster

By studying plant-fungi-bacteria interactions at plant wound sites, the team have identified a natural process stimulated by a hormone released by the wounded plant that would allow synthetic genes to move across organisms and out into the wild.

The bacterium Agrobacterium tumefaciens transforms plant tissue as part of its infection process.  This natural process provides an important toolbox for scientists to genetically manipulate many species of plants.  Recently this technology has been developed for non-plant organisms including by the Bailey & Foster Group in Bristol’s School of Biological Sciences.

Their success has come from adding the plant wound hormone acetosyringone, which triggers Agrobacterium transformation mechanisms and allows foreign genes to modify cells (genetic transformation).  In the natural environment Agrobacterium and fungi likely encounter each other at plant wound sites where acetosyringone is present, raising the possibility of natural gene transfer from bacterium to fungus.

Professor Gary Foster and colleagues tested whether transformation of fungi by Agrobacterium can occur in nature on plants.  Their results clearly demonstrate that when placed together on damaged plant tissue, Agrobacterium readily transforms associated fungi.  “This suggests a previously unknown route for horizontal gene transfer in nature,” said Professor Foster.

These results may have implications for the risk assessment of GM plants generated via Agrobacterium-mediated transformation.  Agrobacterium can survive within following artificial transformation in tissue culture, and can be detected within regenerated transgenic plants.  This research shows that these have the potential to move the same genetic modifications to fungi in a natural environment.

Prior to release of a GM plant, elimination of Agrobacterium following modern genetic modification is a key concern of geneticists and policy makers as it is essential to prevent later escape of synthesised gene from Agrobacterium to other organisms. 

Professor Foster said: “This study suggests that the encounter between Agrobacterium and a fungus on the plant surface may lead to gene flow in a previously overlooked way, potentially leaking GM genes into the natural world.”

Explore further: Heaven scent: Finding may help restore fragrance to roses

More information: The Bristol study, published online in PLoS ONE, was carried out with financial support from NERC.

Related Stories

Evolutionary origin of bacterial chromosomes revealed

Mar 26, 2009

Researchers have unveiled the evolutionary origin of the different chromosomal architectures found in three species of Agrobacterium. A comprehensive comparison of the Agrobacterium sequence information with the genome sequences ...

With fungi on their side, rice plants grow to be big

Jun 10, 2010

By tinkering with a type of fungus that lives in association with plant roots, researchers have found a way to increase the growth of rice by an impressive margin. The so-called mycorrhizal fungi are found ...

Scientists unravel the genetic coding of the pea

Feb 26, 2008

The pea is one of many important crop species that is unsuited to the Agrobacterium-based genetic modification techniques that are commonly used to work with crops. Researchers, reporting in the open access journal Genome ...

Fungi important in Arctic nitrogen cycle

May 09, 2006

U.S. biologists say a new method of calculating nitrogen transfer from mushrooms to plants is proving that fungi is important in the Arctic nitrogen cycle.

Plant gene clusters for natural products

Mar 20, 2008

John Innes Centre scientists have found that plants may cluster the genes needed to make defence chemicals. Their findings may provide a way to discover new natural plant products of use as drugs, herbicides ...

Recommended for you

Study on pesticides in lab rat feed causes a stir

Jul 02, 2015

French scientists published evidence Thursday of pesticide contamination of lab rat feed which they said discredited historic toxicity studies, though commentators questioned the analysis.

International consortium to study plant fertility evolution

Jul 02, 2015

Mark Johnson, associate professor of biology, has joined a consortium of seven other researchers in four European countries to develop the fullest understanding yet of how fertilization evolved in flowering plants. The research, ...

Making the biofuels process safer for microbes

Jul 02, 2015

A team of investigators at the University of Wisconsin-Madison and Michigan State University have created a process for making the work environment less toxic—literally—for the organisms that do the heavy ...

Why GM food is so hard to sell to a wary public

Jul 02, 2015

Whether commanding the attention of rock star Neil Young or apparently being supported by the former head of Greenpeace, genetically modified food is almost always in the news – and often in a negative ...

The hidden treasure in RNA-seq

Jul 01, 2015

Michael Stadler and his team at the Friedrich Miescher institute for Biomedical Research (FMI) have developed a novel computational approach to analyze RNA-seq data. By comparing intronic and exonic RNA reads, ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.