Gene expression changes in interspecific Festuca x Lolium hybrids

Polyploidy has been recognized a major force in the evolution of flowering plants. Allopolyploidy involves a merge of distant genomes followed by whole-genome duplication. Although recently formed allopolyploids retain duplicated copies of a majority of genes on homoeologous chromosomes, it appears that the contribution of parental genomes doesn’t need to be equal and that altered gene expression is common. Such a divergence is believed to develop in two phases. The first takes place immediately after the hybrid formation, while the second is a gradual evolution of gene expression mediated by diversification of duplicated genes. We have sequenced transcriptomes of two grass species, Festuca pratensis and Lolium multiflorum. The sequences were used to identify species-specific SNPs, which were located in the parental genomes. Developed SNP platform was used to analyze gene expression in newly synthesized Festuca × Lolium hybrids. This provided novel data on genome interactions and silencing of genes belonging to the parental genomes.