Abstract
Early steps in myelination in the central nervous system (CNS) include a specialized and extreme form of cell spreading in which oligodendrocytes extend large lamellae that spiral around axons to form myelin. Recent studies have demonstrated that laminin-2 (LN-2; α2β1γ1) stimulates oligodendrocytes to extend elaborate membrane sheets in vitro (cell spreading), mediated by integrin α6β1. Although a congenital LN-2 deficiency in humans is associated with CNS white matter changes, LN-2-deficient (dy/ dy) mice have shown abnormalities primarily within the peripheral nervous system. Here, we demonstrate a critical role for LN-2 in CNS myelination by showing that dy/dy mice have quantitative and morphologic defects in CNS myelin. We have defined the molecular pathway through which LN-2 signals oligodendrocyte cell spreading by demonstrating requirements for phosphoinositide 3-kinase activity and integrin-linked kinase (ILK). Interaction of oligodendrocytes with LN-2 stimulates ILK activity. A dominant negative ILK inhibits LN-2-induced myelinlike membrane formation. A critical component of the myelination signaling cascade includes LN-2 and integrin signals through ILK.
Original language | English (US) |
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Pages (from-to) | 397-408 |
Number of pages | 12 |
Journal | Journal of Cell Biology |
Volume | 163 |
Issue number | 2 |
DOIs | |
State | Published - Oct 27 2003 |
Keywords
- Dy/dy mice
- Focal adhesion
- ILK
- LN-2
- PI3K
ASJC Scopus subject areas
- Cell Biology