Recent advances in the use of genetically encodable optical tools to elicit and monitor signaling events.
                            
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                                cyan
                            
                                red
                            
                                UV
                            
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                                BLUF domains
                            
                                Cryptochromes
                            
                                Fluorescent proteins
                            
                                LOV domains
                            
                                Phytochromes
                            
                                UV receptors
                            
                            
                            
                            Review
                            
                            
                            
                        
                        
                        
                        
                            Abstract:
                            Cells rely on a complex network of spatiotemporally regulated signaling activities to effectively transduce information from extracellular cues to intracellular machinery. To probe this activity architecture, researchers have developed an extensive molecular tool kit of fluorescent biosensors and optogenetic actuators capable of monitoring and manipulating various signaling activities with high spatiotemporal precision. The goal of this review is to provide readers with an overview of basic concepts and recent advances in the development and application of genetically encodable biosensors and optogenetic tools for understanding signaling activity.