Fig. 4

(a) Scheme of the light-induced expression of mCherry-TCP, which interacts with rtTAm, and then the complex binds to tetO elements in TRE3G promoter. (b) Light-induced expression of mCherry-TCP. One group of cells was not illuminated by blue LED (Red line). The rest three groups of cells were illuminated by blue LED (1.25 W m⁻²) for 24 h followed by further 48 h (72 h in total, orange line), 24 h (48 h in total, green line), or 0 h (24 h in total, blue line) incubation in a dark environment. (c) mCherry-TCP induced expression of luciferase. The luciferase expression levels of the above cells were examined. “0 h” represents cells without illumination, “24 h” represents cells illuminated for 24 h without further incubation in the dark, “48 h” represents cells illuminated for 24 h then incubated in dark for further 24 h, “72 h” represents cells illuminated for 24 h then incubated in dark for 48 h. The data are presented as mean ± SEM (n = 6). (d) Scheme showing the cumate-inducible expression of rtTAm and EYFP. (e) Cumate-inducible expression of EYFP examined by flow cytometry. The corresponding cumate concentrations are indicated