The overall goal of this project is to artificial chromosome technology in plants. Artificial chromosomes have the potential to stack genes of benefit to agriculture and basic plant genomics studies on an independent chromosome that can be made to specification. Procedures to add new genes to pre-existing artificial chromosome platforms will be developed that can continue to make amendments in perpetuity. Secondly, methods will be tested that allow much larger numbers of genes to be added to a minichromosome in a single increment than is currently possible. Thirdly, the combination of artificial chromosomes with haploid breeding to introduce the minichromosomes into multiple new varieties more efficiently will be developed. Fourthly, a test of pollen selection to maximize the transmission of artificial chromosomes from one generation to the next will be conducted. Artificial or engineered minichromosomes have the potential to provide a pre-determined site of transgene integration into a plant genome rather than the random nature of plant transformation that is currently used. The targeted insertion will avoid the potential mutagenic effect and gene silencing that often results from uncontrolled integrations. Moreover, the potential now exists that many different genes determining several plant characteristics can be transformed at once onto a minichromosome that can be further modified and that is independent of the normal chromosomes. With the use of artificial chromosomes it should be possible to introduce whole biochemical pathways to add new properties to plants that would facilitate maximizing the ultimate yield or to use plants as factories for the inexpensive production of useful proteins or metabolites. For basic studies, artificial chromosomes provide the means to generate chromosomes to specification that will facilitate the study of chromosome behavior and gene expression among other subjects.
The amount of arable land on earth has been static for some time but the global population continues to increase. If the world standard of living is to remain as is or improve, the amount of food produced by agricultural endeavors will need to increase over the coming decades. Many new developments will be needed to address this issue but novel means of manipulating plant genomes is thought to be a major contributor to this effort. The development of plant artificial chromosome platforms and their enhancement might help with this problem. The procedures developed should be easily adapted to other plant species and thus can serve as a model system for transfer to them. Training will involve diverse undergraduate and graduate students in plant genomics and biotechnology. Information about this project and its outcomes can be accessed at the project website (http://maizeminichromosomes.missouri.edu) and MaizeGDB. These include detailed information about project objectives, results, participants, publications as well as biological resources produced such as vectors and maize lines and the protocols used to generate them. In addition, links to YouTube videos illustrating the techniques involved in the project will be accessible through the project website, MaizeGDB and ResearchGate (www.researchgate.net/).
