Fig. 2.

Transactivation of PID by tissue-specific cell extracts. (A) Total protein purified from mixed stage flowers (F), siliques (Sl), rosette leaves (L), 10-day-old seedling shoots (S), or roots (R) was incubated with GST:PID or GST:MPID. PID labeling was detected by autoradiography after PAGE. (B) GST-PID was phosphorylated by tissue-specific protein extracts as described in A, washed, and incubated with MBP to assess PID activity. Incorporation of γ-³²P by MBP was quantified by using a liquid scintillation counter. Data are representative of three independent experiments; error bars represent standard error. Autoradiographs were exposed for 12 h.