Evolution of AGPase duplicates

ADP-glucose pyrophosphorylase (AGPase), a key enzyme in starch biosynthesis, is comprised of large (LSU) and small (SSU) sub-units encoded by multiple paralogous genes in angiosperms. Corbi et al. investigate the patterns of molecular evolution of AGPase genes following duplications. They find that both coevolution among amino acid residues located in between-sub-unit interaction domains or within the highly constrained SSU, and repeated subfunctionalization events under the ‘Escape from Adaptive Conflict’ model have contributed to AGPase evolution.