(A) Schematic of the mouse genomic locus of Nlgn1 showing the target site of Cas9. sgRNA sequence is underlined, and replaced bases in knock-in mice are capitalized. (B) DNA sequence electropherograms of WT and knock-in heterozygote mouse. Red arrow indicates the amino acid substitution from proline to leucine (CCA to CTA of residue 89), and blue arrow indicates a silent mutation for genotyping using restriction enzyme BsrBI. (C-D) Western blots of cortex, hippocampus, and cortical synaptosomal fractions from wild-type, Nlgn1 P89L heterozygote, and homozygote mutant mice. (WT n = 3, heterozygote n = 4, homozygote n = 3) Data are represented as means ± S.E.M. (*p<0.05, **p<0.01 Tukey-Kramer’s multiple comparisons test).