Supporting data for “Bioenergetics study of NADP-ME type C4 plant Setaria viridis using in planta ATP sensors”

I introduced the genetically encoded ratiometric fluorescence MgATP2- biosensor (AT1.03) with a maize ubiquitin (Ubi) promoter to different cellular compartments of NADP-ME subtype C4 plant Setaria viridis. My works showed that ATP concentration in the chloroplasts was always low comparing to the cytosol, and the ATP level of BS cells was higher than that of MS cells in both stroma and cytosol. Upon illumination, stromal ATP concentrations in MS and BS cells both increased instantly due to photosynthesis activity, but stromal ATP was rapidly consumed by the metabolic activities in chloroplasts when light was withdrawn. Promoter-GUS study on two chloroplast ATP/ADP transporters in Setaria viridisgenome (SvNTT1 and SvNTT2) showed that SvNTT1 preferably expressed in mature BS cells, guard cells and root, while SvNTT2 preferred to express in young MS and BS cells. Chloroplasts ATP import assay showed that chloroplasts isolated from young MS and BS cells and mature BS cells can import exogenous ATP into the stroma. Taken together, these results suggest that the increasing expression level of SvNTT1 in BS cells with maturity could provide extra ATP for the Calvin-Benson-Bassham (CBB) cycle. By contrast, the decreasing expression level of SvNTT2 in MS cells chloroplasts with maturity could reduce ATP expenditure at night in mature MS cells and to force the export of malate from MS chloroplasts to balance the ATP/NADPH ratio, which in turn drives malate transport to BS cells to supply NADPH for BS chloroplasts via ME and NADH for BS mitochondria for ATP synthesis. In summary, by employing the AT1.03 biosensors on C4 plant Setaria viridis, we provide a clearer picture on ATP and energy flows in MS and BS cells of NADP-ME type C4 plant S. viridis.