Fig. 1

Conditional Dnmt3b deletion in CA1 neurons of dorsal hippocampus impairs object-place recognition memory. a Representative image showing virus infection (GFP expression) in dCA1 neurons at 14d after injection. b Quantitative RT-PCR showing relative Dnmt3b (left), Dnmt1 (middle) and Dnmt3a (right) mRNA expression in the hippocampus. Unpaired t test, n = 5 for control-virus group and n = 8 for Cre-virus group. c Cre-expressing Dnmt3b^flox/flox mice showing NPR memory deficits with normal NOR memory. Left, Illustration of NPR and NOR behavior paradigms. Middle, NPR test. Right, NOR test. Two-way ANOVA followed by Sidak’s multiple comparisons test, n = 5 for control-virus group and n = 8 for Cre-virus group. dDnmt3b deletion in CA1 of dorsal hippocampus did not affect anxiety-like behavior. Two-way ANOVA followed by Sidak’s multiple comparisons test, n = 11 for control group and n = 18 for Cre-virus group. e The heatmap of differentially expressed genes. f Quantitative RT-PCR analysis showing increased Kcne2 expression after Dnmt3b deletion. Two-way ANOVA followed by Bonferroni posttests. gDnmt3b deletion blocked dynamic changes of Dnmt1 and Dnmt3a mRNA expression induced by NPR training and test. Left,Dnmt1 expression. Right, Dnmt3a expression. One-way ANOVA followed by Tukey’s multiple comparisons test, n = 6 for control group at home cage, n = 7 for control group at 1 h after NPR test, n = 9 for Cre-expressing group at home cage, n = 10 for Cre-expressing group at 1 h after NPR test. ^∗P < 0.05, ^∗∗P < 0.01, and ^∗∗∗P < 0.001 indicates significant difference between compared groups. All data are present as means ± SEM