Fig. 1

Sos1, but not Sos2, depletion significantly affects the transcriptional signature of primary MEFs. (A) Pairwise comparisons of differential gene expression among different Sos1/2 genotypes. A set of 12 independent chip microarray hybridizations (n = 3 independent sample per genotype) were performed using RNA extracted from actively growing primary MEFs belonging to the indicated genotypes. The heatmaps show the results of hierarchical clustering and multiclass comparisons identifying the upregulated (red) and downregulated (blue) probesets that showed significant differential expression at stringent conditions (FDR = 0.05) when comparing Sos1/2^WT primary MEFs with the rest of experimental groups. Total number of repressed (blue) and upregulated (red) differentially expressed probesets detected in these comparisons is indicated on top of each heatmap. Values in each horizontal chart indicate -Log P. (B) Venn diagrams display the relations between the lists of differentially expressed genes (DEGs) in the three sets of comparisons. (C) Functional annotation of DEGs. Text on the left side of the graphs identify functional categories that are enriched at elevated statistical significance within the lists of DEGs (red: overexpressed; blue: repressed) included in the clusters identified in Sos1/2^WT-Sos1^KO and Sos1/2^WT-Sos1/2^DKO pairwise comparisons. The bars represent the percentage of the total number of differentially expressed repressed (blue) or overexpressed (red) gene probe sets ascribed to specific groups of genes of each of the above dendrograms that were identified as significantly enriched (hypergeometric p-values in italics)