Knockdown of OGT precludes memory-dependent increases in O-GlcNAcylation. (A) Schematic of intra-CA1 siRNA infusion timeline (B) Fluorescence microscopy images of red-labeled siRNAs. (C) Quantification and representative images of OGT western blots after siRNA knockdown (n = 4 for all groups; Student's t-test, P = 0.0138) (D) Quantification of OGT mRNA after knockdown in CA1 ((n = 4 for all groups; Student's t-test, P = 0.0016) and retrosplenial cortex (negative control; n = 4 for all groups, P = 0.9890) after infusion of siRNA (E) Schematic of intra-CA1 siRNA infusion followed by training in contextual fear conditioning (F) Quantification of OGT, O-GlcNAc, and NUP62 western blots after OGT RNAi and training in context fear conditioning (O-GlcNAc and NUP62: n = 7, 7, 6; One-way ANOVA with Fisher's exact test, * denotes P < 0.05); (OGT: n = 6, 6, 5; One-way ANOVA with Fisher's exact test, * denotes P < 0.05).