Working group session:
Breeding and Applied Genomics
Presentation type:
oral
Authors:
Grover, Corrinne E; Gallagher, Joseph P; Grupp, Kara K; Wendel, Jonathan F
Presenter:
Grover, Corrinne E
Correspondent:
Grover, Corrinne E
Abstract:
Polyploid speciation is exceptionally common in plants, often operating sympatrically to saltationally generate new lineages. The reunion between two diverged diploid genomes during hybridization and polyploidization sets in motion a wide spectrum of genetic and genomic phenomena whose mechanistic underpinnings remain mostly mysterious and that have largely unknown evolutionary consequences. Recent research has demonstrated that polyploids display diverse responses to genomic merger and doubling, including but not limited to: sequence elimination, alterations of epigenetic marks, gene silencing, activation of genes and retroelements and intergenomic gene conversion. Despite these substantial gains in understanding the consequences of hybridization and genome doubling, our lingering inability to integrate across scales, from molecular genetic responses to ecological and evolutionary consequences, may reflect our focus on single response components (e.g., genes) that do not operate in isolation, but instead function in complex interacting networks. Here we detail our research which seeks to address this next step, focusing on the evolutionary consequences of allopolyploid speciation on pathways and networks. Using the cotton genus (Gossypium) as a well-developed model for studies of polyploidy, we can begin to describe the effects of genome merger and doubling on several interconnected components of the anthocyanin biosynthetic pathway and flowering time network both at the level of the genome and the transcriptome. Here we present our initial results regarding the genomic and transcriptomic responses of an entire network to genome merger and doubling. In addition, we present our progress in addressing the response of the complex flowering time network to intense directional selection, which was practiced by early domesticators to transform cotton from a wild, photoperiod-sensitive, perennial antecedent into a day-length neutral, annualized row crop.