Publication: Polysialylation increases lateral diffusion of neural cell adhesion molecule in the cell membrane.

Publié dans: Journal of Biological Chemistry, 2007, Epub ahead of print. ⟨10.1074/jbc.M608590200⟩

Auteurs: Fabien Conchonaud, Stéphane Nicolas, Marie-Claude Amoureux, Céline Ménager, Didier Marguet, Pierre-François Lenne, Geneviève Rougon, Valéry Matarazzo

Résumé

Polysialic acid (PSA) is a polymer of N-acetylneuraminic acid residues, added post-translationally to the membrane bound Neural Cell Adhesion Molecule (NCAM). The large excluded volume created by PSA polymer is thought to facilitate cell migration by decreasing cell adhesion. Here we used live cell imaging (Spot Fluorescence Recovery After Photobleaching and Fluorescence Correlation Spectroscopy) combined to biochemical approaches in an attempt to uncover a link between cell motility and the impact of polysialylation on NCAM dynamics. We show that PSA regulates specifically NCAM lateral diffusion, and this is dependent on the integrity of the cytoskeleton. However, whereas the GDNF chemotactic effect is dependent of PSA, the molecular dynamics of PSA-NCAM is not directly affected by GDNF. These findings reveal a new intrinsic mechanism by which polysialylation regulates NCAM dynamics and thereby a biological function like cell migration.

Lien vers HAL – hal-00165536

Lien vers le DOI – 10.1074/jbc.M608590200