Figure 9.

A model of how Arabidopsis WRKY63 is involved in vernalization-induced flowering. Without vernalization, WRKY63 can activate FLC expression by direct targeting. During vernalization, the binding of WRKY63 is increased in the promoters of the lncRNAs COOLAIR and COLDAIR, resulting in COOLAIR and COLDAIR activation. Therefore, the expression of FLC is repressed by increased COOLAIR and COLDAIR during vernalization. Furthermore, WRKY63 can also activate the expression of other vernalization-induced genes.