Controlling Axonal Polarization using Micropatterns

BISBAL M; ROTH S; BROCARD J; BUGNICOURT G; ANDRIEUX A; VILLARD C

Creta

Workshop; Cell Biology of the Neuron: Polarity, Plasticity and Regeneration; 2011

EMBO

Neurons are highly polarized cells, which contain a single long axon and severaldendrites, dedicated to the transmission and processing of information. Being ableto trigger in vitro the axonal fate of one given undifferentiated neurite is an issuefaced by neural network engineering that could also improve our knowledge ofaxonal polarization. Here we described a protocol of neuronal culture that allowsthe manipulation of axonal differentiation. This achievement resulted from ourability to constraint neuronal shape through its cell body and neurites, with theuse of non-specific adhesion and original micropatterns. By controlling neuronpolarity of hippocampal neurons we were able to reach more than 85% ofdifferentiation along the predicted direction, providing a simple tool for thedesign of in vitro networks with a control of the inter-cellular information flow.Beyond their striking control of axonal differentiation, these patterns have provedto be apt tools to explore biological mechanisms associated with theestablishment of polarity in neurons. In particular, our results indicated that thecentrosome location was not predictive of axonal polarization but rather followedaxonal fate. Also the possibility to tune neuritic curvature revealed a role ofmechanical tension during axonal differentiation. Finally, pharmacologicalstudies suggested that microtubules, but not actin cytoskeleton, were involved inthe triggering of tension-mediated neuronal polarization.