Protein kinase C (PKC) is a family, which consists of at least ten subtypes. To elucidate subtype-specific functions of PKC, we have developed the methods to observe PKC translocation in real time and in the living state using PKC fused with fluorescent proteins, including GFP and DsRed. Based on the live imaging of PKC translocation, we have demonstrated that PKC showed stimulus- and subtype-specific translocation, which can recognize its specific substrate and induce its specific cellular response (PKC targeting). These findings suggest that PKC targeting is the molecular basis underlying the diversity of PKC functions. Live imaging of PKC translocation has been proved to be a beneficial tool for understanding not only PKC functions, but also PKC-mediated signal transduction pathways. We have further analyzed PKC functions in the central nervous system using transgenic mice, which can express PKC-GFP in a brain-region-specific manner.