A new method of constructing artificial plant chromosomes from small rings of naturally occurring plant DNA can be used to transport multiple genes at once into embryonic plants where they are expressed, duplicated as plant cells divide, and passed on to the next generation -- a long-term goal for those interested in improving agricultural productivity.
In the October 19, 2007, issue of PLoS-Genetics, a team of academic and commercial researchers show that their "maize mini-chromosomes" (MMC) can introduce an entire "cassette" of novel genes into a plant in a way that is structurally stable and functional. Early results, the study authors say, "suggest that the MMC could be maintained indefinitely."
"This appears be the tool that agricultural scientists, and farmers, have long dreamed of," said Daphne Preuss, PhD, professor of molecular genetics and cell biology at the University of Chicago and chief scientific officer and president of Chromatin, Inc., the makers of the MMCs.
"This technology could be used to increase the hardiness, yield and nutritional content of crops," she said. "It could improve the production of ethanol or other biofuels. It could enable plants to make complex biochemicals, such as medicines, at very little expense."
It could also "cut one to two years out of any new transgenic project," said Preuss, who is taking a leave of absence from the University to bring this technology into the marketplace. "You get a better product faster, which saves time, reduces costs, and frees up resources."
The production of transgenic plants, including maize, has historically relied on techniques that integrate DNA fragments into a host chromosome. This can disrupt important native genes or lead to limited or unregulated expression of the added gene.
Currently, to add a single gene, plant scientists create hundreds of transgenic plants in which the new gene is randomly inserted into a plant chromosom
|Contact: John Easton|
University of Chicago Medical Center