122 RODERMEL ET AL.Figure 4 Rubisco,RbcS, and rbcL mRNA abundances during development in the wild-type and antisense
plants. Measurements of relative amounts of Rubisco (A), RbcS mRNA (B), and rbcL mRNA (C) were
performed on all the leaves from wild-type and antisense plants with either 40% (Mutant 1) or 20% (Mutant 2)
of wild-type Rubisco amounts. Leaf 15 is the youngest leaf at the top of plant just prior to flowering, and leaf
6 is the oldest leaf still remaining at the bottom of the plant. Each data point represents the means ( SD) of
three measurements from three different plants; abundances were calculated relative to the maximum value in
the wild type. For the protein assays, soluble proteins were isolated from frozen leaf disks and electrophoresed
through discontinuous 12.5% sodium dodecyl sulfate (SDS) polyacrylamide gels. Proteins were loaded on the
gel on a leaf area basis. The gels were immunoblotted with tobacco SS and LS antibodies, and band intensities
on the filters were quantified by phosphorimage analysis. LS and SS gave similar results; LS data are shown.
To determine transcript abundances, RNAs were isolated from frozen leaf disks and equal amounts were
applied to slot blot filters. The filters were probed with RbcS and rbcL gene-specific probes. The filters were
quantified by phosphorimage analysis. (Adapted from Ref. 13.)