C4 photosynthesis: 50 years of discovery and innovation

Abstract

It is now over half a century since the biochemical characterization of the C₄ photosynthetic pathway, and this special issue highlights the sheer breadth of current knowledge. New genomic and transcriptomic information shows that multi-level regulation of gene expression is required for the pathway to function, yet we know it to be one of the most dynamic examples of convergent evolution. Now, a focus on the molecular transition from C₃-C₄ intermediates, together with improved mathematical models, experimental tools and transformation systems, holds great promise for improving C₄ photosynthesis in crops.

Keywords: 14C pulse chase; C3–C4 intermediate species; C4 crops; C4 photosynthetic pathway; C4 rice project; CO2 fixation; Hal Hatch and Roger Slack; Kranz anatomy.; convergent evolution.