Figure 2: Mood-change-like behavior and the iDG phenotype in α-CaMKII HKO mice. (a) Pattern of locomotor activity of wild-type and α-CaMKII HKO mice in their home cage. Mutant mice were hyperactive and showed a periodic mood-change-like activity pattern. A.U: arbitrary unit. (b) Among the downregulated genes in the hippocampus of α-CaMKII HKO mice, several genes were expressed selectively in the DG (Allen Brain Atlas [42]. Seattle, WA: Allen Institute for Brain Science. © 2004–2008. Available from: http://www.brain-map.org). Graphs indicate the relative expression levels of each gene in the microarray experiment. (c) In α-CaMKII HKO mice, expression of PSA-NCAM (a late-progenitor and immature-neuron marker) and calretinin (an immature neuron marker) was markedly increased, and expression of calbindin (a mature neuron marker) was decreased. (d) Expression of Arc-dVenus in the DG of α-CaMKII HKO mice after the working memory task (eight-arm radial maze test) was completely abolished. Red: calbindin; green: Arc-dVenus. Adapted from Yamasaki et al. [1] and Matsuo et al. [13].