Figure 2

Unsupervised hierarchical clustering of the patterns of variation in expression for 4,218 genes (represented by 4,915 cDNA) in SEG-1 cells at pH 3.5 for 5 or 20 minutes. Each time point was assayed in duplicate. The array dendrogram represents the degree of similarity between arrays. The image uses a color code to represent relative expression levels. Red represents expression levels greater than the mean for a given gene across all samples. Green represents expression levels less than the mean across samples. A color bar (top) relates the color code to the magnitude of the differences in gene expression relative to the all-sample mean for each gene. Grey indicates missing or excluded data.