Figure 2.

Sera raised against the C terminus of REX2 and REX3 recognize a single band in Western blots with 3D7 parasite extracts but not with D10 parasites. D10 and 3D7 parasites were saponin lysed, and the pellet and the supernatant fraction were analyzed by Immunoblotting. When probed with the serum raised against REX2, a single band of 13 kDa was detected in the saponin pellet of 3D7 but not D10 parasites (A). A single band of 39 kDa was observed in the saponin supernatant when probed with the serum raised against REX3 (B). Western analysis of the same samples using a serum against GAPDH demonstrated equal amounts of protein present in D10 and 3D7 parasite and also showed that saponin treatment did not release the contents of the parasite cytoplasm. Size markers are indicated in kilodaltons on the left of each blot.