Quantitative RT-PCR relative gene expression levels. The results of the quantitative RT-PCR validation experiments are shown in the graph. Genes were selected for the RT-PCR analysis based on the results of the microarray analysis, or because of their presence in the cubilin-megalin multiligand endocytic receptor complex. The red bars on the left represent the fold change in the expression of cubilin and cubilin-related genes and the blue bars on the right represent the fold change in the expression of megalin and megalin-related genes relative to the expression of the housekeeping genes Ppil2 and Dctn6. (*p < .05; **p < .01) Error bars represent SEM values. Gene symbols, relative expression levels and p values are provided in the corresponding Table 2. Cubilin (Cubn), Apolipoprotein A1 (ApoA1), Amnionless (Amn), Transferrin (Trf), T-cell immunoglobin and mucin domain containing 2 (Timd2), Megalin (Lrp2), Lipoprotein receptor-associated protein 1 (Lrpap1), Disabled (Dab2), Folate Receptor (Folr1), Retinol Binding Protein 4 (Rbp4), Sonic Hedgehog (Shh), Transthyretin (Ttr).