Fig. 4.

Co-expression network fractionation within metabolic pathways after maize whole genome duplication. a A schematic of a hypothetical co-expression network after a WGD event is illustrated to define potential relationships. Maize1 and maize2 intra-edges indicate the co-expression correlations among genes from the same subgenome. Subgenome inter-edges represent the co-expression relationship between genes which are from different subgenomes. The “lost” genes (in yellow) are those that have been fractionated after the recent WGD event and are missing from one of the subgenomes. Maize1 genes are shown in pink circles, while maize2 genes are in green circles. b-c Examples of co-expression networks in the stearate biosynthetic pathway where all genes were retained and the glycolysis IV pathway in which some duplicate pairs have been fractionated resulting in lost genes. Genes on the right panel encode enzymes corresponding to each pathway on the left