A MALARIA MEROZOITE SURFACE PROTEIN (MSP1)-STRUCTURE, PROCESSING AND FUNCTION

Merozoite surface protein-1 (MSP-1, also referred to as P195, PMMSA or MSA 1) is one of the most studied of all malaria proteins. The protei n is found in all malaria species investigated and structural studies on the gene indicate that parts of the molecule are well-conserved. St udies on Plasmodium falciparum have shown that the protein is in a pro cessed form on the merozoite surface, a result of proteolytic cleavage of the large precursor molecule. Recent studies have identified some of these cleavage sites. During invasion of the new red cell most of t he MSP1 molecule is shed from the parasite surface except for a small C-terminal fragment which can be detected in ring stages. Analysis of the structure of this fragment suggests that is contains two growth fa ctor-like domains that may have a functional role.