Fig. 3

Heatmap and hierarchical clustering of 1242 genes with the most significantly differential expression during postnatal lung development (P < 0.05). Centred and scaled log RNA-seq expression data. Rows in the heatmap represent genes and columns represent samples. The gene tree on the left was generated by hierarchical clustering. Four gene clusters were selected to represent genes with different expression dynamics (k-mean clustering, k = 4, right side). Expression profile of the four major gene expression clusters was during (a) the later alveolar stage of development, b saccular stage of development, c earlier postnatal period with a gradual reduction of expression during the course of development, and (d) early stages of development. The limits of each cluster are represented by grey and white bars along the right side of the heatmap. Cluster A is the largest gene cluster and the expression profile of this cluster is summarized by a dark grey band (min, max log expression) rather than showing independent gene expression as in cluster (b to d). The light grey shaded area represents the range log expression of all the data (1242 genes)