AlphaII-spectrin participates in the surface expression of cell adhesion molecule L1 and neurite outgrowth.
Exp Cell Res
; 322(2): 365-80, 2014 Apr 01.
Article
em En
| MEDLINE
| ID: mdl-24462599
ABSTRACT
AlphaII-spectrin, a basic component of the spectrin-based scaffold which organizes and stabilizes membrane microdomains in most animal cells, has been recently implicated in cell adherence and actin dynamics. Here we investigated the contribution of αΙΙ-spectrin to neuritogenesis, a highly complex cellular process which requires continuous actin cytoskeleton remodeling and cross-talk between extracellular cues and their cell surface receptors, including cell adhesion molecules. Using RNA interference-mediated gene silencing to down-regulate αΙΙ-spectrin expression in human neuroblastoma SH-SY5Y cells, we observed major changes in neurite morphology and cell shape (1) reduced mean length and a higher number of neurites per cell; occasional long neurites were thinner and displayed abnormal adhesiveness during cell migration resulting in frequent breaks; similar persisting adhesiveness and breaks were also observed in trailing edges of cell bodies; (2) irregular polygonal cell shape in parallel with loss of cortical F-actin from neuronal cell bodies; (3) reduction in protein levels of αΙ- and ßΙ-spectrins, but not ßΙΙ-spectrin (4) decreased global expression of adhesion molecule L1 and spectrin-binding adapter ankyrin-B, which links L1 to the plasma membrane. Remarkably, αΙΙ-spectrin depletion affected L1 - but not NCAM - cell surface expression, and L1 clustering at growth cones. This study demonstrates that αΙΙ-spectrin is implicated in normal morphology and adhesive properties of neuron cell bodies and neurites, and in cell surface expression and organization of adhesion molecule L1.
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Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Proteínas de Transporte
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Membrana Celular
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Neuritos
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Molécula L1 de Adesão de Célula Nervosa
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Proteínas dos Microfilamentos
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Neuroblastoma
Limite:
Animals
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Humans
Idioma:
En
Revista:
Exp Cell Res
Ano de publicação:
2014
Tipo de documento:
Article