Fig. 4: Identification of genes involved in pseudonectary formation.

a, b Sampling strategy for RNA sequencing of the S9 petal. I, II, III, and IV represent the sampled four parts. Scale bar: 1 mm. For a, the experiments were repeated three times independently with similar results. Histograms showing the number of genes specifically (c) and preferably (d) expressed in each part. Volcano plots showing differentially expressed genes in Part III relative to Part II (e) and Part IV (f). The up- and downregulated genes are shown with red and blue dots, respectively, while the genes showing no significant expression changes are represented by gray dots. Representative genes homologous to the well-known regulators are highlighted with enlarged dots, with red and blue fronts standing for up- and downregulated genes, respectively, in both comparisons, while black front representing up- or downregulated genes in one comparison. g A Venn diagram showing the numbers of up- and downregulated genes (red and blue, respectively) in the two comparisons shown in e and f. A number of TFs are shown in brackets. h The spatiotemporal expression patterns of representative candidate genes.