FIGURE 5.

Acute responses of RPS6-phosphorylation to light and darkness, heat and cold. All seedlings are wild-type and 12-days-old. Experiments were replicated twice with similar results. (A) Seedlings grown in a LD cycle on 1% sucrose were shifted to darkness at ZT 4 for the indicated times. Control seedlings were maintained in the light. (B) Seedlings grown in a LD cycle on 0% sucrose were subjected to 37°C heat in the light for the indicated times. (C) Seedlings grown in a LD cycle on 0% sucrose were subjected to 4°C in the light for the indicated times. (D) Seedlings grown in a LD cycle on 1% sucrose were transferred to white light for the indicated times. (E) Etiolated seedlings germinated in darkness without sucrose were exposed to the indicated light qualities for 0.5 or 2 h. (F) Same as (E) but in the presence of 1% sucrose. Note that levels of phosphorylation were elevated even in darkness. Absolute signal strength should not be compared with that in other panels because exposure times for the immunoblots differed.