The physiological role of the GTPase Rab21 in neuronal migration and the development of the cerebral cortex.

SEBASTIAN DUPRAZ; MAYRA PEROTTI; FLORENTYNA BUSTOS PLONKA; SANTIAGO QUIROGA; LUCAS J. SOSA

CHICAGO

Congreso; Society for Neuroscience Annual Meeting 2019; 2019

Society for Neuroscience

The development of the complex structure of the mammalian neocortex requires the proper migration of developing neurons from the ventricular zone containing neural progenitors to the cortical plate. The precise coordination of different cellular processes such as cytoskeleton dynamics, membrane trafficking and cell adhesion during migration is achieved by a variety of signaling pathways. GTPases play a central role in all these processes. In this context, the small GTPase Rab21 has been implicated in the regulation of cell adhesion dynamics by controlling the trafficking of endocytic vesicles containing adhesion molecules. Interestingly, Rab21 has been also implicated in neurite outgrowth. In preliminary experiments, we expressed dominant negative Rab21(T31N) in the embryonic cortex by in utero electroporation (IUE). In contrast to controls, neurons expressing Rab21(T31N) were arrested within the VZ/SVZ, indicating an important function for Rab21 in neuronal migration. Notably, the neurons that fail to enter the cortical plate showed increased neurite branching and multipolar morphology. These studies are important to better understand the mechanism governing the development of the cerebral cortex and the mechanisms that participate in neurodevelopmental pathologies such as autism spectrum disorders and cortical malformations.