Figure 4

Expression patterns and functional analysis of each cluster from microarray. Fold change over control cells was calculated for each gene. The fold changes of all genes in each cluster identified by K-means clustering analysis were averaged and plotted as fold change v.s time. The results shown are means ± S.E. Distribution of major functional categories for biological process terms are shown in pie charts. C: control untreated cells; D1-D7; the cells treated with 0.75 μM arsenic for 1–7 days.