Plant & Animal Genomes XI Conference Plant & Animal Genomes XI ConferenceJanuary 11-15, 2003
Town & Country Convention Center
San Diego, CA
Workshop: Comparative Genomics
Narrowed-leaf lupin is the major grain legume grown in Western Australia and plays a pivotal role in crop rotation systems. Lupin improvement programs are focusing on developing new varieties with disease resistance, superior agronomic traits and enhancing the nutritional qualities of the grain. A member of the Leguminoseae family, lupin has a similar genome size and chromosome number to soybean and the finding of Arabidopsis as a ‘bridging’ species across legumes provides a vast resource of genome sequencing information for comparative genomics. As a preliminary investigation for using soybean in comparative genome analysis, RFLP markers from a genetic map of soybean cross-hybridized to lupin DNA indicating that gene sequences are highly conserved and provide ‘landmarks’ to identify the extent to which syntenic units are conserved in lupins. Although a large degree of gene similarity was detected, the extent to which true orthologues exist between species remain unclear. Three lupin genes were isolated and characterized and their gene expression and predicted protein function were compared with soybean and Arabidopsis orthologues. In some cases, the transcription profiles and similarity in the deduced protein sequence indicates a similar function in all species. However, in other cases, genes with similar protein sequence showed differences in protein folding structure, active sites of enzymes and transcription profiles, indicating alternative functions in different species. The implications for using comparative genomic approaches to enhance lupin variety development are discussed.