A dynamic network of transcription during A. thaliana pollen development. The pollen development of A. thaliana ranges from UNM, BCP, TCP, MP, HP, to 0.5 hr pollen tube, and 4 hour pollen tube stages. The transcription factors are represented as a square, and target genes as a circle. Blue or red arrow lines show the influence of a transcription factor on a target gene, positively or negatively. The transcription factors, that are not processed by NCA but collected by text-mining, include AGL18, OFP1, TSO1 and MYB65. The genes with no expression are denoted with green line. 11 clusters are grouped together in total.