Figure 1.
SNpc and VTA dissection from mouse brain.
Brain sections were labeled against tyrosine hydroxylase antibody without (A) and after (B) SNpc dissection, and without (C) and after (D) VTA dissection. Scale bar: 500 µm. E. Relative Calb1 mRNA level. *, p<0.05 comparing VTA to SNpc (n = 4 in each group).
Figure 2.
Volcano plots illustrating differential gene expression in SNpc (A) & VTA (B) comparing late middle-aged (18months old) to young (2month old) mice.
Differentially expressed genes were distributed in the top left and top right sections of each figure, corresponding pFDR <0.05 and fold change<−1.3 and pFDR <0.05 and fold change >1.3, respectively.
Figure 3.
Validation of microarray results in SNpc by real time quantitative PCR.
Relative log2 fold changes of mRNA were presented comparing late middle-aged (18months old) to young (2month old) mice. Positive numbers corresponded to up-regulated genes, whereas negative numbers indicated down-regulated genes. *, p<0.05 comparing 18 to 2 months old mice using Student’s t-test. n = 4 replicates for each age group.
Figure 4.
Representative immunohistochemical staining of GFAP in SNpc.
A and B, immuno-staining against GFAP antibody. A' and B', immuno-fluorescent staining against TH antibody. A'' and B'', merging of immuno-stainings against GFAP and TH antibodies, the later was represented with a pseudo-color. SNpc was highlighted in each panel. Inset, a higher magnification of SNpc for each picture. Scale bar, 200 µm.
Table 1.
Gene ontology analysis of age-dependent genes in SNpc and VTA comparing 18 to 2 months old mice.
Figure 5.
Top 15 biological functions over-represented in aged (≥ 24 months old) mouse brain in comparison to SNpc and VTA in late middle-aged (18 months old) mice.
A. VTA; B. Top 120 probe sets with the lowest pFDR values in VTA. Threshold: p = 0.05.
Table 2.
Age-associated genes specific to mouse SNpc.
Table 3.
Gene ontology analysis of age-associated genes specific to SNpc.