Temporal and spatial transcriptomic and miRNA dynamics of CAM photosynthesis in pineapple ($)

CAM (crassulacean acid metabolism) is the form of photosynthesis in which carbon assimilation occurs at night. CAM allows plants, especially those growing in arid regions, to avoid excessive water loss. With the long-term goal of eventually engineering this water-conserving trait into crop plants, Wai and VanBuren et al. have mapped the patterns of gene expression both temporally and spatially in photosynthetic (green) and non-photosynthetic (white) pineapple leaves. They found that many CAM pathway genes are enriched in clock-associated cis-regulatory regions, which suggests that CAM evolved through neofunctionalization of pre-existing genes. The authors also identified genes likely to be involved in the diurnal cycling of photosynthate from green to white leaf tissues. Plant J. 10.1111/tpj.13630