Figure 3. Switchable flower meristems by conditional accumulation of CO-td.

(a) Conditional expression of CO-td fusion leads to premature flowering in vivo. Four-week-old (I and II) WT and (III and IV) K2:CO transgenic plants grown under permissive and restrictive temperatures and short-day conditions. (III) In transgenic K2:CO plants, plants bolted earlier than in the WT (I). Scale bars, 5 cm. (b) K2:CO protein levels from transgenic plants grown at permissive or restrictive temperature. (c) Stabilization of K2:CO in prt1. The K2:CO fusion protein stabilizes in the prt1 mutant background under restrictive temperature indicating that the E3 ligase PRT1 is required for K2 degradation. For details on N-degron technology, see Supplementary Fig. 1; for construct layout, see Supplementary Fig. 2. For transcript levels under restrictive and permissive conditions, see Supplementary Fig. 4. A developmental time-course experiment for CO-td is shown in Supplementary Fig. 6.