Neuronal polarity: remodeling microtubule organization.

Cell polarization generates morphological and functional asymmetry, and is crucial for the development and proper functioning of many cell types. Recent data have revealed that the microtubule cytoskeleton is a major determinant in the establishment and maintenance of neuronal polarity. Microtubules provide the structural basis for neuronal polarization, because of their intrinsic properties including inherent polarity. Moreover, the polarized microtubule network also forms the basis for selective cargo trafficking into axons and dendrites. Here we review recent studies examining the molecular processes that control microtubule remodeling and polarized cargo sorting, and propose that changes in microtubule organization play an instructive role in the initial polarization.