Fig. 2

CreLite‐mediated recombination in zebrafish embryos. PhyBΔCreC and PIF6CreN gene were subcloned into pCS2+ expression vector for in vitro transcription, A. The resulting CreLite mRNAs, along with the cofactor phycocyanobilin (PCB), were microinjected into ubi:zebrabow zebrafish reporter line, B, which changes its color from red to either cyan and yellow depending on the Cre‐mediated recombination event. Injected embryos were exposed to 660 nm red light for an hour at shield stage, C. Negative controls including no PCB and no light exposure were examined, D. Embryos with both PCB and red light exposure show broad recombination in the animal. Fluorescence was analyzed in different tissues throughout the embryos, while signal from the yolk or yolk extension was excluded due to potential autofluorescence; scale bar = 1 mm. Yellow fluorescent protein (YFP) signal of converted animals shows color conversion in various tissues, E, including brain and otic vesicle (b), lens (l), muscle (m), and epithelial (epi) cells; scale bar = 100 μm