(a) Light-induced NEUROD1 upregulation in human iPSCs using indicated dCas9-activators with four sgRNAs targeting NEUROD1 at day 1. Data are expressed as relative mRNA amount to the negative control transfected with EGFP vector in the dark and represented as mean ± s.e.m. (n=3 cell culture replicates from one of two representative experiments). (b) Immunofluorescence images of human iPSCs expressing CPTS2.0 targeting NEUROD1 with four sgRNAs. Magenta, beta III tubulin; Blue, DAPI. In this experiment, no positive beta III tubulin signal was observed. Immunostaining were performed after 96 h blue light illumination or incubation in the dark. Scale Bar = 50 μm.