FIG. 3.

D10 parasites lack the Pfr2hb gene. (A) D10, 3D7, and HB3 gDNAs were digested with RsaI (R), HinfI (H), or XmnI (X), blotted to HybondN, and probed with the C2 probe. Sizes are in base pairs. (B) D10 and 3D7 gDNAs were digested with AccI (A), NsiI (N), or BstYI (B), blotted to HybondN, and probed with the Pfr2hb-specific probe U1 or the Pfr2ha-specific probe U2. (C) D10 and 3D7 gDNAs were double digested with NsiI/BglII, blotted to HybondN, and probed with a mixture of the single-copy gene dhps (21) and the C1 probe. Either 4, 8, or 24 μl of the digest was electrophoresed on the agarose gel. The dhps fragment was amplified from D10 gDNA using primers 5′-AAGATTAAATTTTCTTG-3′ and 5′-ATATAGAATTGTTACTTTTGTATA-3′. The copy number of the Pfr2ha and -hb genes in 3D7 relative to D10 was determined using a PhosphorImager (Molecular Dynamics).