Optogenetic control of RNA function and metabolism using engineered light-switchable RNA-binding proteins.
                            
                                blue
                            
                            
                                CRY2/CIB1
                            
                                PAL
                            
                                VVD
                            
                            
                                
                                    HEK293T
                                
                            
                                
                                    HeLa
                                
                            
                            
                                Transgene expression
                            
                                Epigenetic modification
                            
                                Endogenous gene expression
                            
                            
                            
                            
                            
                        
                        
                        
                        
                            Abstract:
                            RNA-binding proteins (RBPs) play an essential role in regulating the function of RNAs in a cellular context, but our ability to control RBP activity in time and space is limited. Here, we describe the engineering of LicV, a photoswitchable RBP that binds to a specific RNA sequence in response to blue light irradiation. When fused to various RNA effectors, LicV allows for optogenetic control of RNA localization, splicing, translation and stability in cell culture. Furthermore, LicV-assisted CRISPR-Cas systems allow for efficient and tunable photoswitchable regulation of transcription and genomic locus labeling. These data demonstrate that the photoswitchable RBP LicV can serve as a programmable scaffold for the spatiotemporal control of synthetic RNA effectors.