Related Experiment Video
Updated: Jun 14, 2026

Rapid and Specific Immunomagnetic Isolation of Mouse Primary Oligodendrocytes
Published on: May 21, 2018
Insulin-like growth factor binding protein-1 activates integrin-mediated intracellular signaling and migration in
Daniel Chesik1, Jacques De Keyser, Reinier Bron
1Department of Neurology, University Medical Center Groningen, Groningen, The Netherlands. d.chesik@med.umcg.nl
Abstract:
In multiple sclerosis (MS), oligodendrocytes in lesions are lost, leaving damaged tissue virtually devoid of these myelin-producing cells. Our group has recently demonstrated enhanced expression of insulin-like growth factor (IGF) binding protein-1 (IGFBP-1) in oligodendrocytes (CNPase(+)) localized adjacent to MS lesions. In the present study, we demonstrate IGF-1-independent actions of IGFBP-1 on OLN-93 oligodendroglial cells, including activation of kinases ERK1/2, focal adhesion kinase and p21-activated kinase as well as small monomeric GTPases Rac and Ral. Activation of these intracellular signaling components was inhibited by GRGDS peptide, indicating signaling through integrin receptors. While both IGF-1 and IGFBP-1 demonstrated rapid induction of actin polymerization, IGFBP-1 proved to be a more potent inducer of migration than IGF-1, inducing a threefold increased migration rate. Furthermore, through integrin receptor signaling IGFBP-1 induced rapid transient translocalization of intracellular Rac toward punctuated structures followed by translocation of Rac to the plasma membrane. Our results suggest that up-regulation of IGFBP-1 in oligodendrocytes in MS may serve two functions: (i) regulate IGF-1 actions, (ii) exert IGF-independent effects through its RGD sequence.
Related Concept Videos
Intracellular Signaling Affects Focal Adhesions
Some...
Activation of Integrins
In "outside-in signaling," external factors in the extracellular space bind to exposed ligand binding sites on integrins. This causes the inactive protein to undergo a conformational change to become active. Integrins are often clustered on the cell membrane. Repetitive and regularly spaced ligand binding events provide an effective stimulus.
Integrins
Some ECM proteins assemble into a basement membrane to which the remaining components adhere. Proteoglycans typically form the bulk of the ECM while fibrous proteins, like collagen,...
Regulation of Angiogenesis and Blood Supply
Insulin: The Receptor and Signaling Pathways
Immunoglobulin-like Cell Adhesion Molecules
Ig-CAMs exhibit either homophilic binding (to other Ig-CAMs) or heterophilic binding (to other ligands such as integrins). While most Ig-CAMs...
