Comparative transcriptomics: finding candidate genes responsible for kale domestication

Morphotypes of Brassica oleracea are the result of a dynamic interaction between the genes that regulate the transition between vegetative and reproductive stages and those that regulate leaf morphology and plant architecture. In kales ornate leaf patterns, flowering delaying and nutrient quality are some of the characters were potentially selected by humans during domestication. Understanding candidate genes responsible for kale domestication is of importance to ultimately improve crop production. We aim to identify candidate genes that are responsible for kale leaf shape diversity and the evolution of domestic kale. Here we look at the global pattern of expressed genes during one single phase of development in kale, cabbage and TO1000 to gain an understanding of the genome-wide differences among some of the vegetative B. oleracea phenotypes. We identified gene expression patterns that are shared among the phenotypes and estimate the contribution of morphotype-specific gene expression patterns that set each of them apart. Differentially expressed developmental genes that regulate the vegetative to reproductive transition were abundant and present in all comparisons. Overall design: Three replicates each of Kale and TO1000. Two replicates of Cabbage.