Generation of Dlgap2−/−(KO) mice. (A,B) Deletion of exon 6 in the Dlgap2 gene. (C) The whole brain lysate of Dlgap2−/−mice lacked DLGAP2 protein products. (D) DLGAP2 was detected in the cortex (cor.), hippocampus (hip.), striatum (stria.) and olfactory bulb (olfac.) of Dlgap2+/+ (WT) mice, but not in Dlgap2−/−mice. (E) Dlgap2−/−mice displayed novelty-induced hyperactivity in the open-field test. Data are presented as mean ± standard error of the mean. n =11 for WT and 10 for KO mice. ***P < 0.001 from a two-tailed t-test. bp, base pair; cor., cortex; F1, forward primer 1; hip., hippocampus; KO, knockout; olfac., olfactory bulb; PCR, polymerase chain reaction; R1, reverse primer 1; R2, reverse primer 2; stria., striatum; WT, wild type; FRT, flippase recognition target.