Spatiotemporal Dynamics of Sensory Neuron and Merkel-Cell Remodeling During Epidermal Homeostasis

The study "Spatiotemporal dynamics of sensory neuron and Merkel-cell remodeling are decoupled during epidermal homeostasis" investigates the remodeling of sensory neurons and Merkel cells in the skin's epithelial layer. The research involved imaging of 20 axons in four mice and found that 89% of axon terminals and 63% of Merkel cells showed significant remodeling over the imaging period. The degree of plasticity in axonal terminals was related to that of Merkel cells. The study also found that Merkel-cell numbers decline substantially over a month in adult mice, with 7% of all Merkel cells appearing to be added and 9% relocated within the cluster. The plasticity of Merkel cells, but not axonal remodeling, was found to be synchronized to the rapid epithelial regeneration that occurs during hair growth. The study concludes that Merkel cells stabilize individual branches, suppress exuberant branching, and promote maturation of terminal morphology. The research raises questions about the mechanisms that dictate remodeling sensory axons during epithelial homeostasis and suggests that developmental mechanisms of axonal patterning may remain active to control axonal remodeling in adulthood.