A second merozoite surface protein (MSP-4) of Plasmodium falciparum that contains an epidermal growth factor-like domain.
Merozoite surface proteins of Plasmodium falciparum play a critical role in the invasion of human erythrocytes by the malaria parasite. Here we describe the identification of a novel protein with a molecular mass of 40 kDa that is found on the merozoite surface of P. falciparum. We call this protein merozoite surface protein 4 (MSP-4). Evidence for the surface location of MSP-4 includes (i) a staining pattern that is consistent with merozoite surface location in indirect immunofluorescent studies of cultured parasites, (ii) localization of MSP-4 in the detergent phase in Triton X-114 partitioning studies, and (iii) nucleotide sequencing studies which predict the presence of an N-terminal signal sequence and a hydrophobic C-terminal sequence in the protein. Immunoprecipitation studies of biosynthetically labelled parasites with [3H] myristic acid indicated that MSP-4 is anchored on the merozoite surface by a glycosylphosphatidylinositol moiety. Of considerable interest is the presence of a single epidermal growth factor-like domain at the C terminus of the MSP-4 protein, making it the second protein with such a structure to be found on the merozoite surface.
Marshall
V M
VM
The Walter and Eliza Hall Institute of Medical Research, Melbourne, Victoria, Australia. vmarshal@wehi.edu.au
Silva
A
A
Foley
M
M
Cranmer
S
S
Wang
L
L
McColl
D J
DJ
Kemp
D J
DJ
Coppel
R L
RL
D000595:Amino Acid Sequence; D000818:Animals; D000954:Antigens, Surface / Q000737:chemistry; D001483:Base Sequence; D018076:DNA, Complementary / Q000302:isolation & purification; D004815:Epidermal Growth Factor / Q000737:chemistry*; D017261:Glycosylphosphatidylinositols / Q000032:analysis; D008969:Molecular Sequence Data; D010963:Plasmodium falciparum / Q000737:chemistry*; D015800:Protozoan Proteins / Q000737:chemistry* / Q000235:genetics
D000954:Antigens, Surface; D018076:DNA, Complementary; D017261:Glycosylphosphatidylinositols; D015800:Protozoan Proteins; D004815:Epidermal Growth Factor