Wnt7b is involved in axon differentiation and elongation in hippocampal neurons.

LORENA PAOLA NEILA; SILVANA B. ROSSO

Ciudad de Córdoba

Congreso; XXXIII Reunión Anual de la Sociedad Argentina de Investigación en Neurociencias; 2018

The establishment and maintenance of neuronal polarity and the development of the axon and dendrites are essential steps in neuronal circuit formation and therefore crucial for central nervous system development. The binding of Wnt ligands to Frizzled receptor mayactivate different signaling cascades: Wnt/β-catenin, planar cell polarity (PCP) and Wnt/Calcium pathways. In the present work, we investigated the potential role of Wnt7b in early stages of hippocampals neurons culture. Initially, we identified Fz7 as Wnt7b receptor and observed that Fz7 is present along neurites and mainly at the growth cones. Based on these previous results, we decided to evaluate the contribution of Wnt7b-Fz7 during earlier periods, particularly on axonal growth. Our findings suggest that Wnt7b is involved in the establishment of neuronal polarity and in axonal outgrowth but we not founded these effects when Fz7 is overexpressed in neurons. Also, we showed the specificity of Wnt 7b in this effect by adding SFRP1 (antagonist of Wnts proteins) on the conditional medium. To go further, we examined the intracellular signaling triggered by Wnt7b. Pharmacological inhibition of no canonical pathway reveal that inhibition JNK (PCP pathway) abolished Wnt 7b mediated axonal effects over axonal architecture. More analyses are yet to be performed in order to fully evaluate Wnt7b role on axon development.