Inhibition of parasite growth and abrogation of PfPP1 expression by interfering dsRNA. The dsRNA sequences, and electroporation procedure have been described under Materials and Methods. Infected RBC were transfected with dsRNA against PfPP1 (R) or luciferase (C). Western blot (A) shows loss of PfPP1 by the dsRNA, but no effect on the control PfPP2A. The PP1 monoclonal and PP2A peptide antibodies have been described in Materials and Methods. Hypoxanthine incorporation assay (B) shows an approximately 70% inhibition of parasitic DNA synthesis in PP1-depleted cells, compared to the luciferase antisense-treated control.