Figure 3.

Model of mitochondrial fission induced by the activation of the non-canonical Wnt signaling pathway in dendritic spines. Mitochondrial dynamics. Wnt5a ligand binds to its Fz receptor and activates the Wnt/Ca²⁺ signaling pathway to promote mitochondrial fission in the postsynaptic area. Wnt5a increases intracellular Ca²⁺, following the activation of kinases (PKC and CaMKII) and phosphatases (calcineurin), which in turn activates Drp1 through the regulation of its phosphorylation and dephosphorylation states. Drp1 translocates from the cytoplasm to the mitochondrial surface to induce mitochondrial fission. Mitochondrial movement. The importance of the dendritic distribution of mitochondria in the generation of new spines and synaptic plasticity has been established. Once Drp1 is activated and induces mitochondrial fission, new mitochondria could mobilize to dendritic spines to support the energy demands associated with neural activity.