[Novel method for the single-cell structural analysis of neuronal processes--labeling with viral vectors]

Novel methods for Golgi-stain-like labeling of neurons have been developed by applying molecular biological techniques. Using replication-deficient adenovirus and Sindbis viral vectors expressing membrane-targeted green fluorescent protein (GFP), we visualized the neuronal processes of the infected neurons completely. Furthermore, when sufficiently diluted Sindbis virus solution was injected into the brain, the entire axonal arborization of infected neurons was recovered at a single cell level, giving new insights into neuronal networks. We have also developed the dendritic membrane-targeted GFP by using lentiviral vectors with a neuron-specific promoter. When the dendritic membrane-targeted GFP was applied to the transgenic animal production, the information input site, i.e., the dendrites, of a specific neuron group was visualized perfectly. Since neuronal processes, axons and dendrites, are key structures of neuronal information processing, the molecular biological techniques introduced here are useful for the morphological analysis of neuronal networks and thus helpful for understanding the functional design of the nervous system.