FIGURE 8.

Wnt-5a ligand activates Wnt/Ca²⁺ pathway and induces mitochondrial dynamics in post-synaptic regions. The synaptic architecture of the post-synaptic region is important for synaptic transmission; remodeling modifications and signaling pathways are fundamental for synaptic transmission and plasticity, and therefore the synaptic processes require an amount of energy. A, activation of the noncanonical Wnt signaling pathway through Wnt-5a ligand results in the release of intracellular calcium with the consequent activation of kinases (CaMKII and PKC) and phosphatases (calcineurin), calcium-dependent, followed by the modulation (phosphorylation-dephosphorylation steps) of Drp-1 protein and its accumulation on mitochondria, initiating the processes of mitochondrial fission and mobilization to sites of energy demand. B, increased mitochondrial dynamics involve fission-fusion process and mobilization of mitochondria to the dendritic spines in the post-synaptic region. The normal function of mitochondria ensure adequate energy levels for different cell processes, such as postsynaptic transduction. Wnt-5a has proven to be able to activate the Wnt/Ca²⁺ pathway in the post-synaptic terminals of the CA1 region in rat hippocampus, and this activation appears now to be linked with an increased mitochondrial fission event plus the mobilization of small mitochondria to the required dendritic spine sites.