Abstract
Myelination is a complex process requiring coordination of directional motility and an increase in glial cell size to generate a multilamellar myelin sheath. Regulation of actin dynamics during myelination is poorly understood. However, it is known that myelin thickness is related to the abundance of neuregulin-1 (NRG1) expressed on the axon surface. Here we identify cofilin1, an actin depolymerizing and severing protein, as a downstream target of NRG1 signaling in rat Schwann cells (SCs). In isolated SCs, NRG1 promotes dephosphorylation of cofilin1 and its upstream regulators, LIM kinase (LIMK) and Slingshot-1 phosphatase (SSH1), leading to cofilin1 activation and recruitment to the leading edge of the plasma membrane. These changes are associated with rapid membrane expansion yielding a 35-50% increase in SC size within 30 min. Cofilin1-deficient SCs increase phosphorylation of ErbB2, ERK, focal adhesion kinase, and paxillin in response to NRG1, but fail to increase in size possibly due to stabilization of unusually long focal adhesions. Cofilin1-deficient SCs cocultured with sensory neurons do not myelinate. Ultrastructural analysis reveals that they unsuccessfully segregate or engage axons and form only patchy basal lamina. After 48 h of coculturing with neurons, cofilin1-deficient SCs do not align or elongate on axons and often form adhesions with the underlying substrate. This study identifies cofilin1 and its upstream regulators,LIMKand SSH1, as end targets of a NRG1 signaling pathway and demonstrates that cofilin1 is necessary for dynamic changes in the cytoskeleton needed for axon engagement and myelination by SCs.
| Original language | English |
|---|---|
| Pages (from-to) | 5284-5297 |
| Number of pages | 14 |
| Journal | Journal of Neuroscience |
| Volume | 32 |
| Issue number | 15 |
| DOIs | |
| State | Published - Apr 11 2012 |
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ASJC Scopus subject areas
- Neuroscience(all)
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The actin-severing protein cofilin is downstream of neuregulin signaling and is essential for schwann cell myelination. / Sparrow, Nicklaus; Manetti, Maria Elisa; Bott, Marga; Fabianac, Tiffany; Petrilli, Alejandra; Bates, Margaret Longest; Bunge, Mary B; Lambert, Stephen; Fernandez-Valle, Cristina.
In: Journal of Neuroscience, Vol. 32, No. 15, 11.04.2012, p. 5284-5297.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - The actin-severing protein cofilin is downstream of neuregulin signaling and is essential for schwann cell myelination
AU - Sparrow, Nicklaus
AU - Manetti, Maria Elisa
AU - Bott, Marga
AU - Fabianac, Tiffany
AU - Petrilli, Alejandra
AU - Bates, Margaret Longest
AU - Bunge, Mary B
AU - Lambert, Stephen
AU - Fernandez-Valle, Cristina
PY - 2012/4/11
Y1 - 2012/4/11
N2 - Myelination is a complex process requiring coordination of directional motility and an increase in glial cell size to generate a multilamellar myelin sheath. Regulation of actin dynamics during myelination is poorly understood. However, it is known that myelin thickness is related to the abundance of neuregulin-1 (NRG1) expressed on the axon surface. Here we identify cofilin1, an actin depolymerizing and severing protein, as a downstream target of NRG1 signaling in rat Schwann cells (SCs). In isolated SCs, NRG1 promotes dephosphorylation of cofilin1 and its upstream regulators, LIM kinase (LIMK) and Slingshot-1 phosphatase (SSH1), leading to cofilin1 activation and recruitment to the leading edge of the plasma membrane. These changes are associated with rapid membrane expansion yielding a 35-50% increase in SC size within 30 min. Cofilin1-deficient SCs increase phosphorylation of ErbB2, ERK, focal adhesion kinase, and paxillin in response to NRG1, but fail to increase in size possibly due to stabilization of unusually long focal adhesions. Cofilin1-deficient SCs cocultured with sensory neurons do not myelinate. Ultrastructural analysis reveals that they unsuccessfully segregate or engage axons and form only patchy basal lamina. After 48 h of coculturing with neurons, cofilin1-deficient SCs do not align or elongate on axons and often form adhesions with the underlying substrate. This study identifies cofilin1 and its upstream regulators,LIMKand SSH1, as end targets of a NRG1 signaling pathway and demonstrates that cofilin1 is necessary for dynamic changes in the cytoskeleton needed for axon engagement and myelination by SCs.
AB - Myelination is a complex process requiring coordination of directional motility and an increase in glial cell size to generate a multilamellar myelin sheath. Regulation of actin dynamics during myelination is poorly understood. However, it is known that myelin thickness is related to the abundance of neuregulin-1 (NRG1) expressed on the axon surface. Here we identify cofilin1, an actin depolymerizing and severing protein, as a downstream target of NRG1 signaling in rat Schwann cells (SCs). In isolated SCs, NRG1 promotes dephosphorylation of cofilin1 and its upstream regulators, LIM kinase (LIMK) and Slingshot-1 phosphatase (SSH1), leading to cofilin1 activation and recruitment to the leading edge of the plasma membrane. These changes are associated with rapid membrane expansion yielding a 35-50% increase in SC size within 30 min. Cofilin1-deficient SCs increase phosphorylation of ErbB2, ERK, focal adhesion kinase, and paxillin in response to NRG1, but fail to increase in size possibly due to stabilization of unusually long focal adhesions. Cofilin1-deficient SCs cocultured with sensory neurons do not myelinate. Ultrastructural analysis reveals that they unsuccessfully segregate or engage axons and form only patchy basal lamina. After 48 h of coculturing with neurons, cofilin1-deficient SCs do not align or elongate on axons and often form adhesions with the underlying substrate. This study identifies cofilin1 and its upstream regulators,LIMKand SSH1, as end targets of a NRG1 signaling pathway and demonstrates that cofilin1 is necessary for dynamic changes in the cytoskeleton needed for axon engagement and myelination by SCs.
UR - http://www.scopus.com/inward/record.url?scp=84859544328&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84859544328&partnerID=8YFLogxK
U2 - 10.1523/JNEUROSCI.6207-11.2012
DO - 10.1523/JNEUROSCI.6207-11.2012
M3 - Article
C2 - 22496574
AN - SCOPUS:84859544328
VL - 32
SP - 5284
EP - 5297
JO - Journal of Neuroscience
JF - Journal of Neuroscience
SN - 0270-6474
IS - 15
ER -