Johns Hopkins researchers find axons have dynamic pearl-like structures
Updated
Updated · SciTechDaily · May 2
Johns Hopkins researchers find axons have dynamic pearl-like structures
9 articles · Updated · SciTechDaily · May 2
Studies from 2024-2025 found the pattern in mouse neurons, worms and human cortical neurons, using high-pressure freezing and zap-and-freeze microscopy.
The non-synaptic swellings measured about 250 nanometres across, with 70-nanometre connecting segments, and changed with membrane stiffness, sugar concentration and electrical activity, affecting signal speed.
The findings challenge textbook views of smooth axons and suggest bead-like structures, long linked to injury and neurodegeneration, can also occur in healthy neurons and influence brain signalling.
How might the dynamic structure of axons inspire breakthroughs in artificial intelligence or next-generation bioelectronic devices?
Could the discovery of 'pearl-like' axons unlock new treatments for neurodegenerative diseases or revolutionize how we teach and understand the brain?
Are our foundational neuroscience textbooks due for a rewrite now that axons are known to reshape themselves like strings of pearls?
Dynamic "Pearls-on-a-String" Axon Morphology Revealed by High-Pressure Freezing EM: Implications for Neural Signaling and Parkinson’s Disease
Overview
A groundbreaking 2024 study revealed that axons, previously thought to be smooth cylinders, actually have a dynamic 'pearls-on-a-string' structure governed by membrane mechanics and cholesterol. This unique morphology enhances electrical signal speed and allows neurons to adjust signal transmission through structural plasticity. Cholesterol is essential for maintaining these pearls, and its imbalance disrupts axon shape and slows conduction, contributing to neurodegenerative diseases like Parkinson's. This discovery challenges long-held beliefs, opens new research avenues into brain health and disease, and drives plans to study human brain tissue for early biomarkers and potential therapies targeting membrane mechanics.