Regulation and Evolution of C4 Photosynthesis

C-4 photosynthesis evolved multiple times independently from ancestral C-3 photosynthesis in a broad range of flowering land plant families and in both monocots and dicots. The evolution of C-4 photosynthesis entails the recruitment of enzyme activities that are not involved in photosynthetic carbon fixation in C-3 plants to photosynthesis. This requires a different regulation of gene expression as well as a different regulation of enzyme activities in comparison to the C-3 context. Further, C-4 photosynthesis relies on a distinct leaf anatomy that differs from that of C-3, requiring a differential regulation of leaf development in C-4. We summarize recent progress in the understanding of C-4-specific features in evolution and metabolic regulation in the context of C-4 photosynthesis.