Cartoon of PfRH ligands and characterization in the parasite.

<p>A. Schematic depiction of different members of the PfRH family, showing location of the signal peptide, region of homology among the various RH ligands and the trans-membrane region at the C-termini of the proteins. The bar at the bottom of PfRH5 marks the region of PfRH5 that was expressed in <i>E. coli</i>. B. Expression of a recombinant 43-kDa protein of PfRH5 (rRH5), chosen on the basis of homology with putative binding domains of <i>P. vivax</i> reticulocyte-binding protein 1 (PvRBP1) and PfRH4. Arrow indicates rRH5 after purification on GST-agarose column. C. Western Blot and immunoprecipitation analysis of asynchronous Dd2 parasite lysates with anti-rRH5 antibodies (IM). Pre-immune serum (PI) was used as a negative control. Arrow indicates specific 63 kDA RH5 protein seen in lysates.