Synthetic far-red light-mediated CRISPR-dCas9 device for inducing functional neuronal differentiation.
                            
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                                BphS
                            
                                CRY2/CIB1
                            
                            
                                
                                    HEK293
                                
                            
                                
                                    mouse in vivo
                                
                            
                            
                                Cell differentiation
                            
                                Endogenous gene expression
                            
                                Immediate control of second messengers
                            
                            
                            
                            
                            
                        
                        
                        
                        
                            Abstract:
                            The ability to control the activity of CRISPR-dCas9 with precise spatiotemporal resolution will enable tight genome regulation of user-defined endogenous genes for studying the dynamics of transcriptional regulation. Optogenetic devices with minimal phototoxicity and the capacity for deep tissue penetration are extremely useful for precise spatiotemporal control of cellular behavior and for future clinic translational research. Therefore, capitalizing on synthetic biology and optogenetic design principles, we engineered a far-red light (FRL)-activated CRISPR-dCas9 effector (FACE) device that induces transcription of exogenous or endogenous genes in the presence of FRL stimulation. This versatile system provides a robust and convenient method for precise spatiotemporal control of endogenous gene expression and also has been demonstrated to mediate targeted epigenetic modulation, which can be utilized to efficiently promote differentiation of induced pluripotent stem cells into functional neurons by up-regulating a single neural transcription factor, NEUROG2 This FACE system might facilitate genetic/epigenetic reprogramming in basic biological research and regenerative medicine for future biomedical applications.