A Bioinformatic Approach to Identification of Flowering-Related Genes in Wheat and Barley.

Early flowering is an important trait influencing grain yield and quality in wheat (Triticum aestivum L.) and barley (Hordeum vulgare L.) in high-latitude regions such as western Canada. However, the genetics of this trait in wheat and barley is complex as a large number of genes are known or postulated to be involved in functions or pathways related to the timing of flowering. In addition, molecular characterization of the flowering-related genes remains challenging for large and complex genomes of wheat and barley. The purpose of this presentation is to investigate the usefulness of a bioinformatic approach to identification of flowering-related genes in these crop species. In this two-stage bioinformatic approach, we combined reciprocal BLAST searches and OrthoMCL clustering to identify 900 and 275 putative orthologs in wheat and barley, respectively, from 190 known Arabidopsis [Arabidopsis thaliana (L.) Heynh.] genes related to flowering functions or pathways. The annotated flowering-related genes were clustered into 144 orthologous groups with identification of one-to-one, one-to-many, many-to-one and many-to-many orthology relationships. Our approach was further validated by domain and phylogenetic analyses of flowering-related proteins and  analysis of publicly available microarray data sets for in silico expression profiling of flowering-related genes in Arabidopsis and two crop species. The putative orthologous sequences inferred from known Arabidopsis genes can be confirmed and incorporated into molecular breeding for early flowering and maturing wheat and barley in western Canada and other high-latitude regions.