1983~2013년 식물의 유전자조작과 농업 생명공학

Paul Christou^1, 2,  

¹ ICREA Research Professor, Universitat de Lleida-Agrotecnio Center, Department de Produccio Vegetal i Ciencia Forestal, Av. Alcalde Rovira Roure 191, E-25198 Lleida, Spain
² Institució Catalana de Recerca i Estudis Avançats, Passeig Lluís Companys 23, Barcelona 08010, Spain

Introducing genes into plants to create new commercially-useful varieties may seem like a trivial task today. In the early 1980s however, this was one of the major bottlenecks preventing the fulfillment of an agricultural revolution that began following the discovery and use of restriction enzymes, followed swiftly by the genetic engineering of bacteria for medical and industrial applications. Plant biotechnology has been technology-driven since its inception, and the successful establishment of gene transfer technologies for major crops [1,2,3] was a major breakthrough for the small biotechnology companies that spearheaded developments in the field in the early 1980s. When the soil bacterium Agrobacterium tumefaciens was shown to transfer part of the DNA from a resident plasmid into the plant genome, it did not take long to generate the first model transgenic plants [4,5].

The first key plant transformation patents on A. tumefaciens and biolistics defined the industry and precipitated its transformation and consolidation. Whereas early activities in the field were dominated by start-ups in the US such as Cetus Madison (Agracetus), Agrigenetics, Calgene, Advanced Genetic Systems, Molecular Genetics, and others, as well as Plant Genetic Systems in Belgium and a number of larger, more-established agrochemical companies such as Monsanto, DuPont, Lilly, Zeneca, Sandoz, Pioneer, Bayer, and others, the field is now dominated by a handful of big companies. The first two traits to be commercialized successfully were insect resistance based on Bacillus thuringiensis (Bt) genes and herbicide tolerance. The consolidation and turmoil in the Bt industry [6] provides a good example of the broader landscape of consolidations, mergers, and acquisitions that took place in the plant biotechnology sector as a whole (Figure 1).

Figure 1

Consolidation of commercial activities in plant biotechnology. Evolution of the commercial landscape for Bacillus thuringiensis (Bt) crops. The five major companies currently selling Bt seeds have arisen through a series of mergers, acquisitions, and spin offs/demergers as larger companies segregate their agribusiness interests. Monsanto Co., in its current incarnation, was an agribusiness spin-off from Pharmacia in 2002 following the merger of the original Monsanto Co. (established in 1901) with Pharmacia and Upjohn in 2000. Pharmacia created the new Monsanto as an agribusiness subsidiary in late 2000, and then established it as an independent company in 2002. Bayer CropScience is an agribusiness subsidiary of Bayer AG, formed following the acquisition of Aventis CropScience in 2000. Syngenta formed from the merger of Novartis and AstraZeneca in 2000, both of which were agribusiness spin-offs generated in previous mergers. Dow AgroSciences is a wholly owned subsidiary of Dow Chemical Co., formed when Dow Chemical Co. purchased Eli Lilly's stake in Dow Elanco (an agribusiness spin-off from Dow Chemical Co. and Ely Lilly & Co. formed in 1989). Finally, Pioneer Hi-Bred International is now an agribusiness subsidiary of DuPont, which acquired 20% of the company in 1997 and the remaining 80% in 1999. Reproduced, with permission, from [6].

Interestingly, commercial products were developed first and the underpinning science came later. Therefore, it is not surprising that the two original traits remain the most dominant commercial traits today. There have been improvements in efficiency and the traits have been stacked into individual varieties but, in principle, the technology remains the same.

The decision of the academic community to focus on the model plant Arabidopsis thaliana paid handsome dividends in terms of fundamental science. In hand with advances in DNA sequencing, the field of genomics came of age and now it is considered routine to embark on major sequencing projects for different plant species. Access to the gene sequences of major crops can now be combined with high-throughput transcriptome and proteome analysis leading to unprecedented advances in gene discovery and functional annotation. Metabolomics and systems biology are now taking center stage, generating huge amounts of data, using this to create models of the entire plant systems. Advances in bioinformatics allow the storage, handling, mining, and manipulation of these large datasets leading to further advances in our understanding of fundamental and more complex plant processes. The impact of this rich stream of previously untapped data is that targets that were formerly considered intractable, such as the modulation of photosynthesis and the ability of plants to fix nitrogen, are now within our reach as shown by the recent substantial investments of time and resources into these areas. Multigene engineering has also helped to advance the development of crops with more complex traits, including extended metabolic pathways producing valuable compounds such as β-carotene in the case of Golden Rice [7] and three different vitamins in the case of Multivitamin Corn [8].

One surprising development that was not envisaged in the early days of plant biotechnology was the increasingly antagonistic effect of overzealous regulation. A robust regulatory system for new technologies is required, but this should be based on rational principles and evidence rather than political expediency [9,10]. The current regulatory environment for genetically engineered crops particularly in Europe is hostile, irrational, and full of inconsistencies with the overall effect of seriously hampering progress in science. The early pioneers of genetic engineering in plants foresaw the potential of the technology and its ability to increase yields and address our most challenging social problems, such as poverty and food insecurity. Whereas the technology has progressed in leaps and bounds, the positive impact it could have all over the world is being needlessly wasted. My fervent hope is that it will not take another 30 years for this situation to change.

ACKNOWLEDGMENTS

Research at the Universitat de Lleida is supported by MICINN, Spain (BIO2011-23324; BIO02011-22525; PIM2010PKB-00746); European Union Framework 7 Program-SmartCell Integrated Project 222716; European Union Framework 7 European Research Council IDEAS Advanced Grant (to PC) Program-BIOFORCE; RecerCaixa; COST Action FA0804: Molecular farming: plants as a production platform for high value proteins; Centre CONSOLIDER on Agrigenomics funded by MICINN, Spain.

REFERENCES

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