Fig. 6: PS Intein-based gene expression systems for specific cell targeting.

a Schematic of the two cell targeting criteria. b Schematics of the two constructs encoding the light-controlled gene expression systems with co-expressed mCherry and the EGFP reporter with their respective promoters. The constructs were used for transient transfection of HEK293T cells in (c–e). c Microscopy analysis of the dark and illuminated samples (6 h with 450 nm followed by 24 h in darkness) expressing the constructs shown in (b). d Flow cytometry analysis of the samples corresponding to those shown in (c). Total fluorescence signals (EGFP reporter) for the same number of cells in different samples are shown. Data are presented as mean values +/- SD (n  =  3; independent transfection experiments). Respective light-to-dark contrasts are shown above the bars. e Flow cytometry analysis of the samples shown in (d) for mCherry co-expressed with the systems. Total fluorescence signals corresponding to dark samples expressing the systems are shown. Data are presented as mean values +/- SD (n  =  3; independent transfection experiments). The data were processed as in (d). f Schematic of the three cell targeting criteria. g Schematics of the three constructs encoding the N- and C-parts of the light-controlled Split PS-Intein tTA gene expression system with co-expressed mCherry and mTagBFP2 and the EGFP reporter with their respective promoters. The constructs were used for transient transfection of HEK293T cells in (h–j). h Flow cytometry analysis of the dark and illuminated samples (6 h with 450 nm followed by 24 h in darkness) expressing the constructs shown in (g). Total fluorescence signals (EGFP reporter) were analyzed and processed as in (d). Data are presented as mean values +/- SD (n  =  3; independent transfection experiments). Respective light-to-dark contrasts are shown above the bars. i Flow cytometry analysis of the samples shown in (h) for mCherry co-expressed with the C-part of the gene expression system placed under TNF-α-inducible NFκB promoter. Total fluorescence signals corresponding to dark samples expressing the N-part of the system from hTERT promoter are shown. The data were processed as in (d). Data are presented as mean values +/- SD (n  =  3; independent transfection experiments). Respective light-to-dark contrasts are shown above the bars. j Flow cytometry analysis of the samples shown in (h) for mTagBFP2 co-expressed with the N-part of the gene expression system placed under either BIRC5 or hTERT promoters. Total fluorescence signals corresponding to dark samples expressing the C-part of the system (TNF-α-treated samples) are shown. The data were processed as in (d). Data are presented as mean values +/- SD (n  =  3; independent transfection experiments). Respective light-to-dark contrasts are shown above the bars. Arb. units, arbitrary units. Source data are provided as a Source Data file.