Fig. 12

METTL3 overexpression rescues AβO-induced cognitive impairment and synaptic deficits in vivo. WT C57BL/6 mice receiving bilaterally stereotaxic injections of AAV-METTL3/AAV-Ctrl into the hippocampus at ~ 2 months of age were administrated with AβO preparations 2 weeks later. Behavioral tests were performed 2 week after AβO treatment. Cognitive functions were measured by Y maze task (A-B), novel object recognition test (NOR) (C) and object location test (OLT) (D). Locomotor function (E) and exploring activity (F) were measured by open field test (OF) (n = 10 mice/group, sex matched). (G-K) Dendrites (G) and spines (H) in the infused hippocampal areas were examined by Golgi stain. Number of dendrites (I), total length of dendrites (J) and number of dendritic spines (K) were measured. (n = 25 neurons from 5 mice in each group) (*p < 0.05, **p < 0.01, ***p < 0.001; A-F, I-K, one-way ANOVA with bonferroni’s correction)