How competition shapes developing neuromuscular circuits

How does the nervous system adjust its wiring as it develops? Our new paper in Nature Neuroscience reconstructed complete wiring diagrams (connectomes) between motor neurons and muscle fibers in mice from birth to adulthood, and found that the ordered patterns in which motor neurons are recruited help determine which synaptic connections are maintained and which are eliminated. As a co-author, Ju Lu helped develop a mathematical model to explain why some muscle fibers can maintain two distant input synapses, whereas most fibers only have one. These results provide new evidence that the activity patterns of developing circuits play a fundamental role in shaping their mature connectivity. See this news article and the original research paper for more details.