Plant & Animal Genomes XV Conference

January 13-17, 2007
Town & Country Convention Center
San Diego, CA

Syntenic Relationships Between Medicago truncatula And Crop Legumes

Simon R Ellwood¹ , Huyen T Phan¹ , Rebecca Ford² , Matthew Nelson³ , John A Irwin⁴ , Richard P Oliver¹

¹  Australian Centre of Necrotrophic Plant Pathogens, Murdoch University, Perth, Western Australia, 6150, Australia

²  BioMarka, University of Melbourne, Parkville, Victoria, 3010, Australia

³  School of Plant Biology, University of Western Australia, Perth, Western Australia, 6009, Australia

⁴  School of Integrative Biology, University of Queensland, Brisbane, Queensland, 4072, Australia

For many legumes, genetic maps tend to be focused on selected lines and traits in a given agricultural context. In order to produce maps with a broader applicability, we have used the extensive sequence data from the model legume Medicago truncatula to produce orthologous markers. Orthologous markers that are transferable between distantly related legume species also allow for the rapid generation of genetic maps in species where there is little pre-existing genomic or EST information.
Among the Papilionoideae, we compared ESTs from the phylogenetically distant M. truncatula, Lupinus albus, and Glycine max species to produce >600 intron-targeted amplified polymorphic markers (ITAPs). In addition, 126 M. truncatula cross-species markers from Department of Plant Pathology, University of California (USA), and a variety of species-specific markers were included. These markers were used to generate comparative genetic maps of lentil (Lens culinaris Medik.), narrow-leafed lupin (L. angustifolius), and white lupin (Lupinus albus Linn.). We are currently producing maps in broad bean (Vicia faba), and lucerne (M. sativa).
An overview of the effectiveness of different marker types will be presented, as well as the contribution of completed maps to a more thorough understanding of syntenic patterns between M. truncatula and cultivated legumes. This research provides explanations for differences in legume genomes through chromosomal rearrangements and genome duplications, and has also enabled several genes of agricultural interest to be placed in syntenic contexts. Such genes may now be isolated via positional cloning through identification of tightly linked markers, and possible candidate gene(s) for a trait.