TITLE

Marker free transgenic plants: engineering the chloroplast genome without the use of antibiotic selection

AUTHOR(S)
Daniell, H.; Muthukumar, B.; Lee, S. B.
PUB. DATE
February 2001
SOURCE
Current Genetics;Feb2001, Vol. 39 Issue 2, p109
SOURCE TYPE
Academic Journal
DOC. TYPE
Article
ABSTRACT
Chloroplast genetic engineering offers several advantages over nuclear transformation including high levels of gene expression and gene containment. However, a consequence of placing a transgene in the chloroplast genome is that the antibiotic resistance genes used as selectable markers are highly amplified. Engineering genetically modified (GM) crops without the use of antibiotic resistance genes should eliminate the potential risk of their transfer to the environment or gut microbes. Therefore, the betaine aldehyde dehydrogenase (BADH) gene from spinach was used in this study as a selectable marker. The selection process involves conversion of toxic betaine aldehyde (BA) by the chloroplast BADH enzyme to non-toxic glycine betaine, which also serves as an osmoprotectant. Chloroplast transformation efficiency was 25-fold higher in BA selection than with spectinomycin. In addition, rapid regeneration was obtained. Transgenic shoots appeared within 12 days in 80% of leaf disks (up to 23 shoots per disk) under BA selection compared to 45 days in 15% of disks (1 or 2 shoots per disk) under spectinomycin selection. Southern blots confirmed stable integration of foreign genes into all of the chloroplast genomes (10,000 copies per cell) resulting in homoplasmy. Transgenic tobacco plants showed 15- to 18-fold higher BADH activity at different developmental stages than untransformed controls. Transgenic plants were morphologically indistinguishable from untransformed plants and the introduced trait was inherited stably in the subsequent generation. This is the first report of genetic engineering of the higher plant chloroplast genome without the use of antibiotic selection. The use of naturally occurring genes in spinach for selection, in addition to gene containment, should ease public concerns regarding GM crops.
ACCESSION #
15653834

 

Related Articles

  • New trends in bioanalytical tools for the detection of genetically modified organisms: an update. Michelini, Elisa; Simoni, Patrizia; Cevenini, Luca; Mezzanotte, Laura; Roda, Aldo // Analytical & Bioanalytical Chemistry;Oct2008, Vol. 392 Issue 3, p355 

    Despite the controversies surrounding genetically modified organisms (GMOs), the production of GM crops is increasing, especially in developing countries. Thanks to new technologies involving genetic engineering and unprecedented access to genomic resources, the next decade will certainly see...

  • Future Shock. Toffler, Alvin // New Scientist;10/31/98, Vol. 160 Issue 2158, p28 

    Discusses the move toward genetically modified (GM) food crops as of October 1998. Areas where genetically engineered crops of soya bean, maize, oilseed rape and potatoes are growing; When scientists began manipulating the genes of bacteria; The debate about the pros and cons of living in a GM...

  • Brave New Rose. Concar, David // New Scientist;10/31/98, Vol. 160 Issue 2158, p30 

    Discusses the future of genetically modified plants as of October 1998. Mention of a dream of plant engineers to create easy-to-pulp trees; The effort under way to engineer potatoes to double up as vaccines; Suggestion that timber and pulp will increasingly come from high-technology plantations...

  • Introduction to ISBGMO12: biosafety research past, present and future. Raybould, Alan; Quemada, Hector; Romeis, Jörg // Transgenic Research;Dec2014, Vol. 23 Issue 6, p911 

    An introduction is presented in which the editor discusses various reports published within the issue which include genetically modified (GM) crops, the molecular analysis of genetic changes in GMs, and the concerns about hte effects of weedy or invasive GM crops.

  • The technologies for genetic transformation of cereals. Danilova, S. D. // Russian Journal of Plant Physiology;Sep2007, Vol. 54 Issue 5, p569 

    In this review, the analysis of the most widely used technologies for genetic transformation of cereals is presented. The required conditions for transformation, regeneration, and testing of cereal crops are discussed, and a new Agrobacterium tumefaciens-mediated transformation approach is...

  • Is opposition to GM crops science or politics? Trewavas, Anthony J.; Leaver, Christopher J. // EMBO Reports;Jun2001, Vol. 2 Issue 6, p455 

    This article investigates into the arguments that genetically modified (GM) crops pose a particular threat to the environment. As with many new technologies, people are keen to embrace the benefits but reluctant to accept potential risks. The manner of introduction of GM crops onto the market...

  • Vintage genetic engineering. DeFrancesco, Laura // Nature Biotechnology;Mar2008, Vol. 26 Issue 3, p261 

    The article provides information on the effects of genetic engineering on grapes in the U.S. According to the author, the grapevine genome is the first fleshy fruit crop and one of only four flowering plants to be sequenced. He added that genome of the grapes are highly heterogeneous due to its...

  • The Threat of Genetically Modified Organisms (Part 2 of 2). Nacci, Giuseppe // Gerson Healing Newsletter;Jul/Aug2006, Vol. 21 Issue 4, p5 

    The article presents the second part of a two-part series report citing the threats of genetically modified organisms. These threats include intoxification by poisons synthesized from transgenic plants, possibility of global famine due to Terminator technology, and the irreversible disappearance...

  • Growers fear loss of GM crops' potential. Swallow, Andrew; Abel, Charles // Farmers Weekly;10/24/2003, Vol. 139 Issue 17, p45 

    Reports that farm growers across Great Britain fear the results and media coverage of the farm-scale evaluation of genetically modified herbicide tolerant (GMHT) crops as of October 2003. Importance of GM technology for the competitiveness of British growers; Need for the use of the technology...

Share

Read the Article

Courtesy of THE LIBRARY OF VIRGINIA

Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics