Colorful connectome

Ju Lu/Harvard University

In order to understand how each nerve cell integrates into the functional organization of a neural circuit, it is necessary to obtain the complete wiring diagram (connectome) of the circuit by tracing out all the neural processes in the sample. We used confocal laser scanning microscopy to image all the axons that innervate a small ear muscle in transgenic mice that express fluorescent protein in motor neurons. Shown here is one of the reconstructed image stacks containing branches of ~ 10 axons. Each axon was traced out in a semi-automated image processing program and rendered in 3D with a distinct color. This image stack is representative of the hundreds of image stacks from which the entire connectome was reconstructed.