Global co-expression networks and gene modules. a Dendrogram from gene co-expression network analysis. Each module of co-expressed genes was assigned a color and number (ME1 to ME9); b Left: heat map of genes in ME8 showing the spatio-temporal expression pattern after hierarchical clustering. The expression values for each gene are arranged in the heat map, ordered first by anagen, then by catagen and last by telogen; c Changes in testosterone contents levels in different months. P values were calculated by unpaired t-test. *** indicate P value < 0.005; d Correlation between module membership and gene significance in the Blue module; e The top 40 genes defined by the highest intramodular connectivity and their associated genes are shown in the network view. Nodes and size are based on the extent of intramodular connectivity. Larger nodes are highly connected within a module and have greater ‘hubness’.