Plasmodium falciparum rhoptry neck protein 5 peptides bind to human red blood cells and inhibit parasite invasion.
Plasmodium falciparum malaria parasite invasion of erythrocytes is an essential step in host infection and the proteins involved in such invasion are the main target in developing an antimalarial vaccine. Secretory organelle-derived proteins (micronemal AMA1 protein and the RON2, 4, and 5 rhoptry neck proteins) have been recently described as components of moving junction complex formation allowing merozoites to move into a newly created parasitophorous vacuole. This study led to identifying RON5 regions involved in binding to human erythrocytes by using a highly robust, sensitive and specific receptor-ligand interaction assay; it is further shown that the RON5 protein remains highly conserved throughout different parasite strains. It is shown that the binding peptide-erythrocyte interaction is saturable and sensitive to chymotrypsin and trypsin. Invasion inhibition assays using erythrocyte binding peptides showed that the RON5-erythrocyte interaction could be critical for merozoite invasion of erythrocytes. This work provides evidence (for the first time) suggesting a fundamental role for RON5 in erythrocyte invasion.
Universidad de la Sabana, Km. 7, Autopista Norte, Bogotá, Colombia; Universidad del Rosario, Calle 14 No. 6-25, Bogotá, Colombia; Fundación Instituto de Inmunología de Colombia, Carrera 50 No. 26-20, Bogotá, Colombia. Electronic address: hernando_curtidor@fidic.org.co.
Hernando
H
Curtidor
Universidad del Rosario, Calle 14 No. 6-25, Bogotá, Colombia; Fundación Instituto de Inmunología de Colombia, Carrera 50 No. 26-20, Bogotá, Colombia.
Liliana C
LC
Patiño
Universidad del Rosario, Calle 14 No. 6-25, Bogotá, Colombia; Fundación Instituto de Inmunología de Colombia, Carrera 50 No. 26-20, Bogotá, Colombia.
Gabriela
G
Arévalo-Pinzón
Universidad del Rosario, Calle 14 No. 6-25, Bogotá, Colombia; Fundación Instituto de Inmunología de Colombia, Carrera 50 No. 26-20, Bogotá, Colombia.
Magnolia
M
Vanegas
Fundación Instituto de Inmunología de Colombia, Carrera 50 No. 26-20, Bogotá, Colombia; Universidad Nacional de Colombia, Carrera 45 No. 26-85, Bogotá, Colombia.
Manuel E
ME
Patarroyo
Universidad del Rosario, Calle 14 No. 6-25, Bogotá, Colombia; Fundación Instituto de Inmunología de Colombia, Carrera 50 No. 26-20, Bogotá, Colombia.
Manuel A
MA
Patarroyo
D002478:Cells, Cultured; D002942:Circular Dichroism; D004912:Erythrocytes / Q000378:metabolism* / Q000469:parasitology*; D006801:Humans; D017780:Malaria Vaccines / Q000276:immunology; D052940:Merozoites / Q000378:metabolism; D016253:Microscopy, Immunoelectron; D010963:Plasmodium falciparum / Q000276:immunology / Q000378:metabolism* / Q000472:pathogenicity*; D015800:Protozoan Proteins / Q000276:immunology* / Q000378:metabolism*
D017780:Malaria Vaccines; D015800:Protozoan Proteins
Binding; Malaria; Merozoite; Rhoptry neck; Synthetic peptide