Manipulation of endogenous kinase activity in living cells using photoswitchable inhibitory peptides.
                            
                                blue
                            
                            
                                AsLOV2
                            
                            
                                
                                    Cos-7
                                
                            
                                
                                    HEK293
                                
                            
                                
                                    primary mouse cortical neurons
                                
                            
                            
                                Signaling cascade control
                            
                                Control of cytoskeleton / cell motility / cell shape
                            
                            
                            
                            
                            
                        
                        
                        
                        
                            Abstract:
                            Optogenetic control of endogenous signaling can be an important tool for probing cell behavior. Using the photoresponse of the LOV2 domain of Avena sativa phototropin 1, we developed analogues of kinase inhibitors whose activity is light dependent. Inhibitory peptides were appended to the Jα helix, where they potently inhibited kinases in the light but were sterically blocked from kinase interaction in the dark. Photoactivatable inhibitors for cyclic-AMP dependent kinase (PKA) and myosin light chain kinase (MLCK) are described, together with studies that shed light on proper positioning of the peptides in the LOV domain. These inhibitors altered endogenous signaling in living cells and produced light-dependent changes in cell morphodynamics.