Prospects for enhancing leaf photosynthetic capacity by manipulating mesophyll cell morphology

Abstract Leaves are beautifully specialized organs designed to maximize the use of light and CO 2 for photosynthesis. Engineering leaf anatomy therefore brings great potential to enhance photosynthetic capacity. Here we review the effect of the dominant leaf anatomical traits on leaf photosynthesis and confirm that a high chloroplast surface area exposed to intercellular airspace per unit leaf area ( S c ) is critical for efficient photosynthesis. The possibility of improving S c through appropriately increasing mesophyll cell density is further analyzed. The potential influences of modifying mesophyll cell morphology on CO 2 diffusion, light distribution within the leaf, and other physiological processes are also discussed. Some potential target genes regulating leaf mesophyll cell proliferation and expansion are explored. Indeed, more comprehensive research is needed to understand how manipulating mesophyll cell morphology through editing the potential target genes impact leaf photosynthetic capacity and related physiological processes. This will pinpoint the targets for engineering leaf anatomy to maximize photosynthetic capacity. Highlight Cell morphology in leaves affects photosynthesis by controlling CO 2 diffusion and light distribution. Recent work has uncovered genes that control cell size, shape, and number paving the way improved photosynthesis.