Hierarchical cluster analyses of microarray expression data.

<p>Overall cluster analysis of three transcriptome analysis experiments of SK-N-MC cells chronically treated with 5 nM, 50 nM rotenone, or vehicle (0 nM) for 1 week (1 w) and 4 weeks (4 w). Genes significantly altered in the treatment groups were clustered by hierarchical average-linkage analysis and shown in colorgrams depicting the expression level of the genes (rows) in each individual sample (columns). Expression above the mean is displayed in red and below the mean in blue (see normalized scale bar on top). (<b>A</b>) genes significantly altered by 5 nM and 50 nM rotenone at 1 week; (<b>B</b>) genes significantly altered by 5 nM and 50 nM rotenone after 4 weeks. Major cluster are indicated roman numerals and subclusters of genes that show opposite expression pattern at 4 weeks are indicated with arrowheads. The profiles in (<b>C</b>) depict the effects of both rotenone doses across both time points on the relative gene expression in four gene major clusters distinguished by the specific expression change exerted by each dose; the treatment group are indicated at the bottom and the number of changed genes are indicated at the top of each profiles.