Figure 4

Gene co-expression network underlying the GO Biological Process interaction map in obese WAT. The relationships of differentially expressed genes annotated with over-represented categories of the GO Biological Process ontology were determined in order to build a co-expression network. The absolute value of a Spearman's correlation coefficient Rs ≥ 0.8 between expression profiles was used as a co-expression threshold to relate co- or inversely expressed genes. Red lines indicate co-expression relationships while blue lines illustrate inverse expression relationships. Genes with a yellow border code for known ECM components, while genes with a blue border are related to mitochondrial components. The enrichment in genes expressed preferentially in one of the two main cellular fractions of WAT, illustrated in a percentage scale (mature adipocytes in light gray versus SVF in black), was significantly different in the two modules (p value < 0.05). The shapes indicate the module to which the analyzed genes belong: a triangle for Module 1 and a lozenge for Module 2.