A method of creating selective terminable transgenic rice was reported by the scientists of Zhejiang University in this week’s PLoS ONE. Unintended spreading of transgenic rice by pollen and seed dispersal is a major concern for planting transgenic rice, especially transgenic rice expressing pharmaceutical or industrial proteins.
The transgenic rice plants created in the past usually can only be detected by sophisticated molecular detection methods and it is prohibitedly difficult to identify and selectively kill the transgenic rice plants once they escape into environments and contaminate conventional rice.
However, with the technology reported by Dr. Zhicheng Shen’s group, the transgenic rice plants mixed in the conventional rice could be selectively eliminated by a spray of Bentazon, an herbicide commonly used for rice weed control.
This technology appears to be quite simple, reliable and inexpensive for implementation. “If you use Bentazon for weed control in your rice field, you do not need to worry about any possible contamination caused by transgenic rice created by our method. The herbicide will take care of it” said Dr. Shen, the corresponding author of the article. “Containment of transgenic crops only by physical isolation is not sufficient in our view, as human errors, animal activities and nature accidents will lead to the spreading of transgenic rice plants sooner or later” added Chaoyang Lin, graduate student in Dr. Shen’s laboratory and one of the leading contributors of the article. Indeed, several major accidents of unintended spreading of the transgenic crops did happen in the past several years in USA.
This technology may be best for use to contain transgenic rice as bioreactors. “While all biotech products today are safe and nutritious, this technology could allow certain crops targeted for industrial, energy or health uses to be grown under controlled conditions and kept separate from other channels” said Nick Duck Vice President of Research for Athenix Corp. in the USA.
The principle beneath this strategy is elegant and simple according to the article. The genes of interest in these transgenic rice plants will be linked with an RNAi cassette which suppresses the expression of the rice detoxification enzyme of Bentazon, rendering the transgenic rice to be sensitive to the herbicide. Conventional rice is highly tolerant to Bentazon.
Dr. Shen’s lab is currently using the technology for developing transgenic rice as well as corn for expression of industrial enzymes and pharmaceutical proteins. “We believe that transgenic crops are the future, and we feel much better knowing that we may release selectively terminable transgenic plants in the future to address the concern of transgene spreading”, said Dr. Shen.
Source: Public Library of Science
Related stories:
First draft of transgenic papaya genome yields many fruits
A broad collaboration of research institutions in the U.S. and China has produced a first draft of the papaya genome. This draft, which spells out more than 90 percent of the plant’s gene coding sequence, sheds new light on the evolution of flowering plants. And because it involves a genetically modified plant, the newly sequenced papaya genome offers the most detailed picture yet of the genetic changes that make the plant resistant to the papaya ringspot virus. The findings appear as the cover article in the journal
Nature.
A common genetic mechanism discovered in nitrogen-fixing plants
Some soil microorganisms are capable of forging associations with plant roots in the form of symbioses. Certain of these relationships play a highly important ecological and agronomic role. Arbuscular mycorrhizal symbiosis (which links a plant to a fungus) thus gives plants a mechanism for improving their supply of water and mineral nutrition.
Scientists ramp up ability of poplar plants to disarm toxic pollutants
Scientists since the early '90s have seen the potential for cleaning up contaminated sites by growing plants able to take up nasty groundwater pollutants through their roots. Then the plants break certain kinds of pollutants into harmless byproducts that the plants either incorporate into their roots, stems and leaves or release into the air.
Discovery in orange cauliflower may lead to more nutritious crops
While orange cauliflower may seem unappealing to some, it has distinct nutritional advantages. Now, Cornell researchers have identified the genetic mutation behind the unusual hue. The finding may lead to more nutritious staple crops, including maize, potato, rice, sorghum and wheat.
Studying How Modified Genes Escape Into Nature
A University of Arkansas researcher and her colleagues are developing a way to examine how the genomes rearrange themselves during hybridization to better pinpoint how genetically modified organisms may behave when they cross with naturally occurring plants.
Switchgrass research aims to create ethanol to power vehicles for $1 per gallon
In his 2006 State of the Union address, President Bush acknowledged the potential for switchgrass as a source of ethanol to reduce the nation’s reliance on foreign oil. Unlike corn, which is currently used for ethanol production, switchgrass can be grown on marginal soils, is useful as wildlife habitat, and requires little use of fertilizers, insecticides or irrigation.
Plants That Can Eat Arsenic
Environmental arsenic pollution is a serious and growing environmental problem, especially on the Indian subcontinent. Researchers at the University of Georgia had, several years ago, used genetic techniques to create "arsenic-eating" plants that could be planted on polluted sites.
Transplanted corn gene protects rice
Kansas State University scientists say they've demonstrated resistance to bacterial streak disease in maize can be transferred to rice.