Extended model of the plant circadian clock, including the multiple targets of TOC1 and the interactions with the ABA signalling pathway. A: The clock model was extended from the previous one (P2011) by including the negative transcriptional regulations of the core clock genes by TOC1 (blue lines) and the up-regulation of TOC1 expression by ABA signalling, as shown in panel B. Elements of the morning and evening loops are shown in yellow and grey, respectively. Proteins are shown only for EC, ZTL and COP1 for simplicity. Post-translational regulation of TOC1 and the EC by GI, ZTL and COP1 is indicated by the dotted red lines. B: Simplified model of ABA signalling, gated by the clock through regulation of ABAR expression. See section “Model description” for more details. Transcriptional and protein regulation are shown by solid and dotted lines, respectively. C: Short description of the newly-introduced connections and elements of the model compared to P2011.