Figure 1.

Microarray analysis of differential gene expression in wild-type and knockout fibroblasts (H-ras^-/-, N-ras^-/- and H-ras^-/-/N-ras^-/-) subjected to serum starvation or stimulation. Graphical representation of numbers of probesets showing differential gene expression in pair-wise SAM comparisons between the microarray hybridization data of WT fibroblasts that were serum-starved for 24 hours (Control) and corresponding microarray hybridization data of fibroblasts of the indicated WT and ras knockout genotypes obtained before (0 h) or after short-term (1 h) or mid-term (8 h) post-starvation incubation of the cultures in the presence of 20% fetal bovine serum (FBS). Four independent microarray hybridizations were performed for all conditions involving WT samples, and at least three independent hybridizations were performed with RNA of each of the different knockout genotypes analyzed. Numbers shown indicate the amount of induced (red) or repressed (green), differentially expressed probesets that were identified in each case using a stringent false discovery rate cut-off parameter value of 0.09.