Figure 6

A transcriptional regulation network for the S. pombe cell cycle. (a) An enhanced model for the transcriptional regulatory network controlling the S. pombe cell cycle. New insights or connections are denoted in red. Connections to novel motifs related to unknown regulators are denoted in green dashed lines. Fkh2* denotes Fkh2 bound to its target promoter. (b-d) Some of the regulatory motifs found in the cell cycle network. (b) Ace2 regulates its targets through a simple direct activation. (c) Ams2, controlled by MBF through the MCB motif, binds the ACCCT box [17]. Different genes have different combinations of these two sites in their promoters. Genes that have both MBF and Ams2 sites are part of a feed-forward loop. (d) Fkh2 regulates itself through a negative feedback loop, while being activated by Mbx1/Sep1/Plo1 complex.