Spatio-temporal pattern recognition of dendritic spines and protein dynamics using live multichannel fluorescence microscopy
Actin-regulating proteins, such as cofilin, are essential in regulating the shape of dendritic spines, and synaptic plasticity in both neuronal functionality as well as in neurodegeneration related to aging. The analysis of the motility of cofilin in fluorescence video-microscopy allows the discovery of its effects on cell functions. However, the flow of cofilin has not been analyzed to date by automatic means. This paper presents a novel automated pattern recognition system to analyze protein trafficking in neurons. Using spatio-temporal information present in multichannel fluorescence videos, the system generates a temporal maximum intensity projection that enhances the signal-to-noise ratio of important biological structures, segments and tracks dendritic spines, and quantifies the flux and density of proteins in spines. The temporal dynamics of spines is used to generate spine energy images which are used to automatically classify the shape of dendritic spines as stubby, mushroom, or thin. By tracking these spines over time and using their intensity profiles, the system is able to analyze the flux patterns of cofilin and other fluorescently stained proteins. The cofilin flux patterns is found to be correlated with the dynamically changing dendritic spine shapes. The results are presented using multichannel fluorescence videos.