In the weeks before and after we’re born, nerve cells race to colonize our developing muscles. There they create connections, known as synapses, through which the electrical signals that control our movements are passed. During this process, different nerve cells compete for space in the highly excitable areas that will activate the muscle. One or other will prevail, maintaining synapses into adult life. Here we see two types of nerve cell (red and green) converging in an adult rat's calf muscle. This model system reveals that the outcome of synaptic competition depends on the pattern of signals sent down each competing nerve cell. Insights like this are helping researchers understand synaptic jockeying in less accessible parts of the nervous system, including the brain, where it plays an important role in learning and memory.
Written by Daniel Cossins
BPoD stands for Biomedical Picture of the Day. Managed by the MRC London Institute of Medical Sciences the website aims to engage everyone, young and old, in the wonders of biomedicine. Images are kindly provided for inclusion on this website through the generosity of scientists across the globe.