Acta Pharmacologica Sinica 2006 September; 27 (9): 1119-1126; doi: 10.1111/j.1745-7254.2006.00362.x

Aim: To study the role of microtubule dynamics and microtubule associated protein 1B (MAP1B) in regulation of the neurite extension in CAD catecholaminergic neuronal cell line.

Methods: The neuritogenesis of the CAD cells was abolished by inhibiting microtubule polymerization with nocodazole and by blocking microtubule depolymerization with taxol. MAP1B and tubulin protein expression was detected by Western blot. Immunofluorescent staining of tubulins was observed by fluorescent and confocal microscopy.

Results: Microtubule dynamics was essential for CAD neurite extension. Dosage analysis revealed that neurite extension was much more sensitive to nocodazole than to taxol, suggesting a functional requirement for highly active microtubule assembly. A remarkable upregulation of MAP1B protein was detected during neurite extension accompanied with increased microtubule stability.

Conclusion: Upregulation of MAP1B leads to the stabilization of newly formed microtubules in the developing neurites, which in turn promotes neurite extension.

Keywords: microtubule stability; microtubule associated protein 1B; neuritogenesis