Figure 3.

Mutant T60-3 lacks both rbcS genes, and can be transformed with either rbcS1 or rbcS2. (A) PCR amplification of rbcS gene regions from total DNA extracted from wild-type (lane 1), mutant T60-3 (lane 2), and rbcS1 and rbcS2 transformants of T60-3 (lanes 3 and 4, respectively). A single pair of oligonucleotides was used to amplify regions of rbcS1 and rbcS2 (753 and 888 bp, respectively) from the end of intron 1 to the middle of exon 4 (Fig. 2). (B) DNA hybridization analysis of EcoRI/HindIII-digested total DNA (5 μg per lane) extracted from wild-type (lane 1), mutant T60-3 (lane 2), and rbcS1 and rbcS2 transformants of T60-3 (lanes 3 and 4, respectively). The filter was probed with a ³²P-labeled 1190-bp PstI fragment containing the 3′-coding region of rbcS2. The probe detects 1.5- and 7.9-kb fragments that contain the 3′ end of rbcS1 or the entire rbcS2 gene, respectively (Fig. 2).