title: A family of chimeric erythrocyte binding proteins of malaria parasites.
abstract: Proteins sequestered within organelles of the apical complex of malaria merozoites are involved in erythrocyte invasion, but few of these proteins and their interaction with the host erythrocyte have been characterized. In this report we describe MAEBL, a family of erythrocyte binding proteins identified in the rodent malaria parasites Plasmodium yoelii yoelii and Plasmodium berghei. MAEBL has a chimeric character, uniting domains from two distinct apical organelle protein families within one protein. MAEBL has a molecular structure homologous to the Duffy binding-like family of erythrocyte binding proteins located in the micronemes of merozoites. However, the amino cysteine-rich domain of MAEBL has no similarity to the consensus Duffy binding-like amino cysteine-rich ligand domain, but instead is similar to the 44-kDa ectodomain fragment of the apical membrane antigen 1 (AMA-1) rhoptry protein family. MAEBL has a tandem duplication of this AMA-1-like domain, and both of these cysteine-rich domains bound erythrocytes when expressed in vitro. Differential transcription and splicing of the maebl locus occurred in the YM clone of P. yoelii yoelii. The apical distribution of MAEBL suggested localization within the rhoptry organelles of the apical complex. We propose that MAEBL is a member of a highly conserved family of erythrocyte binding proteins of Plasmodium involved in host cell invasion.
authors.affiliation: Department of Biological Sciences, University of Notre Dame, Notre Dame, IN 46556-5645, USA.
authors.forename: S H
authors.initials: SH
authors.lastname: Kappe
authors.forename: A R
authors.initials: AR
authors.lastname: Noe
authors.forename: T S
authors.initials: TS
authors.lastname: Fraser
authors.forename: P L
authors.initials: PL
authors.lastname: Blair
authors.forename: J H
authors.initials: JH
authors.lastname: Adams
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000953:Antigens, Protozoan / Q000737:chemistry; D000954:Antigens, Surface / Q000737:chemistry; D002352:Carrier Proteins / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification*; D015815:Cell Adhesion Molecules / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification*; D016384:Consensus Sequence; D016054:DNA, Protozoan / Q000302:isolation & purification; D004375:Duffy Blood-Group System / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification*; D008565:Membrane Proteins / Q000737:chemistry; D051379:Mice; D008807:Mice, Inbred BALB C; D008969:Molecular Sequence Data; D010962:Plasmodium berghei / Q000737:chemistry* / Q000235:genetics*; D010967:Plasmodium yoelii / Q000737:chemistry* / Q000235:genetics*; D015800:Protozoan Proteins / Q000737:chemistry; D012326:RNA Splicing; D011956:Receptors, Cell Surface / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification*; D011993:Recombinant Fusion Proteins / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification; D016415:Sequence Alignment; D014158:Transcription, Genetic
chemical_list: D000953:Antigens, Protozoan; D000954:Antigens, Surface; D002352:Carrier Proteins; D015815:Cell Adhesion Molecules; D016054:DNA, Protozoan; D004375:Duffy Blood-Group System; C066001:Duffy antigen binding protein, Plasmodium; D008565:Membrane Proteins; D015800:Protozoan Proteins; D011956:Receptors, Cell Surface; D011993:Recombinant Fusion Proteins; C090077:apical membrane antigen I, Plasmodium