Fig. 1
From: Enlarged dendritic spines and pronounced neophobia in mice lacking the PSD protein RICH2
Generation and characterization of RICH2 mutant mice. a Illustration of Rich2 gene (Arhgap44 Rho GTPase activating protein 44 [Mus musculus]; NCBI Gene ID: 216831). b Domain-coding exons are numbered and colored as the corresponding domain. Sites for initiation of transcription are marked by triangles and stop codons are marked by asterisks. Insertion of the gene trap vector in exon 1 is shown. c Western blot illustrating knock-out of the two brain specific RICH2 isoforms in whole brain lysate of RICH2 mutant mice. A gene-dosage effect by knock-out of a single copy of RICH2 in heterozygous mice can be seen by a decreased immunoreactive signal in comparison to the whole brain lysate of wild type mice. To confirm specificity of RICH2 bands, recombinant myc-RICH2, overexpressed in NIH-cells was detected by myc- as well as RICH2-antibody at similar molecular weight. d Measuring wet brain weight revealed an increase of approx. 7 % for both genders, whereas body weight remained unchanged (n(♂) = 21 (+/+), 13 (+/−), 13 (−/−); n(♀) = 18 (+/+), 11 (+/−), 12 (−/−)) (One-way ANOVA: (Brain weight male: F2.44 = 12.512, p = 0.000049, Bonferroni post-hoc analysis: RICH2+/+ vs. RICH2+/− p < 0.01, RICH2+/+ vs RICH2−/− p < 0.0001, RICH2+/− vs. RICH2−/− p = 0.357; female: F2.38 = 7.9793, p = 0.0012, post-hoc analysis RICH2+/+ vs. RICH2+/− p = 0.585, RICH2+/+ vs. RICH2−/− p < 0.0001, RICH2+/− vs. RICH2−/− p = 0.072), (Body weight male: F2.44 = 0.47517, p = 0.62493; female: F2.38 = 0.41256, p = 066488)). e Quantitative analysis of Nissl staining from three different animals and three different brain sections of similar planes from each group reveals no significant changes between wild type and knock-out mice. Nissl positive signals of three optic fields of view from each brain region and brain section were counted (scale bar = 300 μm) (unpaired t-test, Cerebellum: df = 2, p = 0.32, t = 4.30; Cortex: df = 2, p = 0.421, t = 4.3026; Striatum: df = 2, p = 0.4574, t = 4.3026; Hippocampus: df = 2, p = 0.8311, t = 4.3026). f Western blot of different tissue lysates from P70 wild type and heterozygous mice (brain, heart, lung, liver and kidney) demonstrate RICH2 to be predominantly present in brain lysates and less so in liver. g Western blot showing RICH2 expression profile in crude protein lysates of several brain - regions. Cortical, cerebellar and hippocampal lysates show most intense RICH2 immunoreactivities (OFB olfactory bulb, CTX cortex, HIP hippocampus, STR striatum, DI diencephalon, MES mesencephalon, CRB cerebellum, BST brain stem). h In situ hybridization also reveals expression of RICH2 mRNA mostly in cortex, cerebellum and hippocampus