Fig. 4: Molecular changes induced by spatial learning training in WT mice are similarly associated with those in untrained Ccny KO mice.

a, b Transcript (a) and protein (b) levels of Ccny in the hippocampus are reduced after original learning in WT mice. Data represent mean ± SEM. *P < 0.05, **P < 0.005 as indicated, Student’s unpaired t test. Ccny mRNA levels (a) were measured by quantitative real-time polymerase chain reaction (qRT-PCR), and CCNY protein expression levels (b) were quantified from the immunoblots (Upper in b). c, d) The number (c) and Venn diagram (d) of differentially expressed genes (DEGs) that are upregulated or downregulated compared to WT mice without training (WT_Basal), to Ccny KO mice without training (KO_Basal), or to WT mice after original learning (WT_OL). e Heatmap of 29 DEGs that are upregulated in both WT mice after original learning and KO mice without training, compared to WT mice without training. The values of log₂CPM were normalized to the value ranges from a minimum of −3.0 to a maximum of +3.0. CPM, counts per million. f The pathway of “regulation of actin cytoskeleton” by the Kyoto Encyclopedia of Genes and Genomes enrichment analysis and the terms “regulation of neuronal synaptic plasticity” and “learning” by the gene ontology analysis are upregulated in WT mice after original learning and in Ccny KO mice without training. g–i Learning-induced changes of actin-related molecules are affected in Ccny KO mice. g Heatmap of genes known to regulate spine morphology, i.e., those involved in the pathways of Rac, Cdc42, and Rho GTPases (listed on the right side of the heatmap). A change in the RNA expression levels was compared between WT and Ccny KO mice before training (Basal), after original learning (OL), and after original and reversal learning (RL). RNA expression levels of each gene are presented as the log₂fold-change relative to Basal of WT. n = 3 mice for each sample group. h Fold-change of log₂CPM for individual genes are plotted in WT and Ccny KO mice. *P < 0.05, **P < 0.005, ***P < 0.0005. i Genes whose transcript levels are increased in WT and further increased in Ccny KO mice (upper) or whose transcript levels are decreased in WT and further decreased in Ccny KO mice (lower) after original and reversal learning compared to those before training (Basal).