Immunoblot and immunoprecipitation assays were performed as previously described with slight modifications (54 (link)). Briefly, 6-day-old seedlings were treated with 100 μM JA for 6 h, and then roots were collected and ground in liquid nitrogen. The CK2mut seedlings were pre-treated with 1 μM Dex for 24 h before JA treatment. Proteins were extracted in RIPA buffer [50 mM Tris–HCl (pH 7.5), 150 mM NaCl, 1% Triton X-100, 0.1% SDS, 0.5% sodium deoxycholate, 10 mM NaF, 10 mM β-glycerophosphate, 1 mM sodium orthovanadate, 1 mM PMSF, 5 μg/mL leupeptin, 1 μg/mL aprotinin, 1 μg/mL pepstatin]. Anti-GFP antibody (Santa Cruz) was used to detect MYC2-GFP proteins. For immunoprecipitation assays, protein extracts were pre-incubated for 1 h at 4°C with Protein A agarose (Roche), and then incubated for 4 h at 4°C with Anti-GFP agarose conjugate (Santa Cruz). Immunocomplexes were washed five times with RIPA buffer and eluted by adding 4 × SDS loading buffer followed by 5 min of boiling. The anti-phospho-(Ser/Thr) antibody (Abcam) was used to detect the phosphorylated isoform of MYC2. All the experiments were performed three times and showed similar results.