Fig. 5.

Recombinational loss of the aadA-resistance gene in bleached leaf sectors. Two green (G1 and G2) and two white (W1 and W2) leaf sectors from plants treated as shown in Fig. 2G were comparatively analyzed by DNA gel blot analyses. (A) Hybridization of undigested and SalI-digested DNA samples to an aadA-specific probe detects recombined-out pRB115 plasmids as well as aadA copies integrated into the plastid genome (compare with Fig. 4). (B) After digestion with XhoI or BamHI, hybridization to a psbA-specific probe detects identical fragments in green sectors, white sectors, and wild-type leaves (Wt). XhoI digestion produces a fragment of 8.5 kb; BamHI digestion generates a 4.8-kb fragment.