Fig. 2
From: Novel gene sets improve set-level classification of prokaryotic gene expression data
Example of transcription-factor based gene sets. a A transcription factor Fur regulates altogether 130 genes including positively regulated genes e.g., sucA, sucD and negatively regulated genes e.g., cyoB, sucB, sucC, entD. All these regulated genes constitute the gene set. b A complex regulon defined by genes sucA, sucD, sucB and sucC can be divided into two strict regulons defined by two pairs of genes (sucA, sucD) and (sucB, sucC). All the three mentioned regulons are regulated only by a common set of transcription factors CRP, ArcA, IHF, Fur and FNR