Figure 4.

Model of FLC reactivation in Lov-1. The proposed phases of FLC silencing and reactivation. Schematic of the FLC gene, showing the histone modifications in different epigenetic states. (Red flags) H3K27me3; (green flags) H3K36me3. VIN3 is necessary for the nucleation of PHD–PRC2, which is associated with H3K27me3 in the nucleation region of FLC. Spreading of the PRC2 results in H3K27me3 modifications along the whole gene. The green arrow at the right shows the Lov-1-specific reactivation step. Transitions between these states are simulated in the mathematical model. The blue background indicates the cold-dependent transitions.