Unwrapping new layers of complexity in axon/glial relationships

• Published in: Glia Vol. 29; no. 2; pp. 112 - 117
• Main Authors: Witt, Andrea, Brady, Scott T.
• Format: Journal Article
• Language: English
• Published: New York John Wiley & Sons, Inc 15.01.2000
• Subjects: Animals; Axons - metabolism; Central Nervous System - cytology; Central Nervous System - metabolism; Cytoskeleton - genetics; Cytoskeleton - metabolism; Gene Expression - physiology; Humans; Life Sciences (General); Mice; Mice, Neurologic Mutants; Myelin Sheath - metabolism; Myelin Sheath - physiology; Neuroglia - cytology; Neuroglia - metabolism; saltatory conduction; Schwann Cells - cytology; Schwann Cells - physiology; Space life sciences; Non-Nasa Center; Nasa Discipline Neuroscience; Review; Review, Tutorial; NASA Discipline Neuroscience; Non-NASA Center
• ISSN: 0894-1491; 1098-1136
• DOI: 10.1002/(SICI)1098-1136(20000115)29:2<112::AID-GLIA3>3.0.CO;2-Z

Traditionally, myelin has been portrayed as merely playing structural and supportive roles in the nervous system, providing the "insulation" that allows saltatory conduction of the action potential. In 1979, Aguayo and colleagues demonstrated that the axon diameter changes locally in the absence of compact myelin. In 1992, DeWaegh and colleagues proposed a mechanism by which myelin could increase the axon caliber through increased phosphorylation of axonal neurofilaments, although no specific components in this pathway were identified. Subsequent studies confirmed earlier results and recent reports have begun to map out pathways for Schwann cell/axon signaling. Advances in our understanding of local modulation of axons by myelinating glia have begun to offer insights into mechanisms and demonstrated that the influence of myelin on neuronal structure and function is even more complex than first indicated.