Figure 1

dnRAR mice displayed Dox-dependent expression of dnRAR and down-regulation of RARβ expression in the forebrain. (A) Schematic representation of Dox-dependent regulation of dnRAR in the forebrain. (B) Experimental design. Schedule for the treatment of dnRAR mice with Dox. The mice were treated with Dox throughout their lifetime (OFF) or until they were 8 weeks old (OFF - transgene ON; OFF/ON). OFF/ON-dnRAR mice were treated again with Dox for 4 weeks following the withdrawal of Dox for 4 weeks (OFF/ON/OFF). (C) Northern blot analysis of dnRAR mRNA in the forebrain and hippocampus of dnRAR H06 and H02 mice and WT littermates (WT). The upper and lower panels shows the expression of dnRAR mRNA (2.8 kbp) and GAPDH mRNA (1.3 kbp) as an internal control, respectively. (D) Western blot analysis of dnRAR protein in the hippocampus of dnRAR H06 mice and WT littermates. The upper panel shows the expression of a 50-kDa protein corresponding to dnRAR. The upper arrow indicates non-specific binding and the lower arrow indicates dnRAR protein. The lower panel shows the expression of α-tubulin as an internal control. (E) Northern blot analysis of RARβ mRNA in the forebrain of dnRAR H06 and H02 mice and WT littermates. The lower panel indicates the quantification of RARβ mRNA levels in the forebrain of dnRAR H06 and H02 mice and WT littermates (WT, n = 8; H06, n = 8; H02, n = 8). The levels of RARβ mRNA were normalized according to the GAPDH signal. *p < 0.05, compared with WT littermates. (F) qRT-PCR analysis of RARβ mRNA in the hippocampus of dnRAR H06 and H02 mice and WT littermates. Quantification of RARβ mRNA levels in the hippocampus of OFF/ON-dnRAR H06 mice, OFF/ON/OFF-dnRAR H06 mice, and WT littermates (WT, n = 29; OFF/ON, n = 24; OFF/ON/OFF, n = 16). The levels of RARβ mRNA were normalized according to the levels of GAPDH mRNA. *p < 0.05, compared with the other groups. Error bars indicate SEM.