The effects of Wnt7b signalling on axonal morphology

NEILA, LORENA PAOLA; SILVANA B. ROSSO

Villa Carlos Paz, Córdoba

Congreso; XXXIV Reunión Anual SAN 2019; 2019

In the nervous system, Wnts secreted molecules plays important roles in the formation offunctional neuronal circuits by regulating axón pathfinding and remodeling, dendriticdevelopment and synapse assembly. One of the roles of Wnts proteins in the regulation of the cytoskeletal network is essential on some aspects of neuronal maturation, establishment andmaintenance of neuronal polarity and the development of the axon and dendrites. It has beenproved that the Wnts directly regulate the dynamic and organization of microtubules. In thiswork, we evaluate the potential role of Wnt7b during earlier periods of neuronal development,particularly on axonal growth. Our findings suggest that Wnt7b is specific involved in theestablishment of neuronal polarity and in axonal outgrowth. To go further, we examined theintracellular signaling triggered by Wnt7b. Pharmacological inhibition of no canonical pathwayreveals that inhibition JNK (PCP pathway) abolished Wnt7b mediated axonal effects overaxonal architecture. Consistently, we then demonstrated the activation of JNK by western blotand directly by immunofluorescence analyses. More analyses are yet to be performed in orderto determine whether the effect of the Wnt7b on axonal morphology was due to regulation ofmicrotubule stability mediated by JNK. And to continue with the characterization we willevaluate the contribution of small Rho GTPases, which has been implicated in the regulation ofmicrotubule dynamic.