FIG. 4.

Northern (A) and Western (B) analyses of chloroplast transformants. Total RNAs (20 μg) from the mutants indicated at the top were electrophoretically separated, blotted onto Nylon membranes, and hybridized with either a radiolabeled psbD- or rbcL-specific DNA probe. Total proteins (corresponding to 7 μg of chlorophyll) from the mutants were separated by SDS-PAGE, blotted onto filters, and immunolabeled with antibodies against either D1 or PsaD. The triangle marks a serial dilution of wild-type proteins. The autoradiogram was overexposed to allow detection of low D1 levels down to 10%. High D1 levels were quantitated from a less-exposed autoradiogram.