Ectopic myelinating oligodendrocytes in the dorsal spinal cord as a consequence of altered semaphorin 6D signaling inhibit synapse formation.
Journal Article
Different types of sensory neurons in the dorsal root ganglia project axons to the spinal cord to convey peripheral information to the central nervous system. Whereas most proprioceptive axons enter the spinal cord medially, cutaneous axons typically do so laterally. Because heavily myelinated proprioceptive axons project to the ventral spinal cord, proprioceptive axons and their associated oligodendrocytes avoid the superficial dorsal horn. However, it remains unclear whether their exclusion from the superficial dorsal horn is an important aspect of neural circuitry. Here we show that a mouse null mutation of Sema6d results in ectopic placement of the shafts of proprioceptive axons and their associated oligodendrocytes in the superficial dorsal horn, disrupting its synaptic organization. Anatomical and electrophysiological analyses show that proper axon positioning does not seem to be required for sensory afferent connectivity with motor neurons. Furthermore, ablation of oligodendrocytes from Sema6d mutants reveals that ectopic oligodendrocytes, but not proprioceptive axons, inhibit synapse formation in Sema6d mutants. Our findings provide new insights into the relationship between oligodendrocytes and synapse formation in vivo, which might be an important element in controlling the development of neural wiring in the central nervous system.
Full Text
Duke Authors
Cited Authors
- Leslie, JR; Imai, F; Fukuhara, K; Takegahara, N; Rizvi, TA; Friedel, RH; Wang, F; Kumanogoh, A; Yoshida, Y
Published Date
- September 2011
Published In
Volume / Issue
- 138 / 18
Start / End Page
- 4085 - 4095
PubMed ID
- 21831918
Pubmed Central ID
- 21831918
Electronic International Standard Serial Number (EISSN)
- 1477-9129
International Standard Serial Number (ISSN)
- 0950-1991
Digital Object Identifier (DOI)
- 10.1242/dev.066076
Language
- eng