rsf1 mutants have wild-type levels of phyA and phyB. Proteins were extracted from 6-d-old seedlings, separated on 8% (w/v) SDS-PAGE gels, and blotted onto nitrocellulose. The membrane was probed with mAA1-3 or mBA2, monoclonal antibodies directed against phyA and phyB, respectively (Shinomura et al., 1996). The amido black-stained membrane is shown as a loading control. A, Seedlings were grown for 6 d in continuous 8 μmol m−2 s−1 FR light. B, Seedlings were grown for 6 d in the dark, or for the same total duration of which the last 1, 2, 4, or 15 h was in constant 100 μmol m−2 s−1 R light. C, Seedlings were grown for 6 d in the dark.