Fig. 3

Hierarchical clustering analysis of 515 selected genes expression during glucoamylase fermentation. a Each horizontal line displays the expression data for one gene after normalization (the mean of FPKM value at one time point divided through the maximum of mean FPKM value for each gene) at time points as indicated. The color scale at the top left represents the normalized expression level (0–1). The highest expression of each gene is therefore defined as 1 (dark red color). Color bars in the middle indicate defined sub-branches according to the height of the tree. The genes assigned to each cluster are listed in Table c1–c12. b Gene expression profiles analysis. c1 to c12 represent the twelve clusters indicated orderly by the color bars in Fig. 3a. Mean and standard error of the normalized expression data of genes in each cluster at the four time points were used to plot the curves. The number of genes found in each cluster is indicated by the value of n