Fig 1.
Phylogenetic tree of dbpII from the 19 most predominant P. vivax haplotypes.
Haplotypes with > 1% frequency were used here: accession numbers (haplotype). P. vivax dbp: EU812840.1 (H1), EU812841.1 (H2), EU812842.1 (H3), EU812844.1 (H4), EU812845.1 (H5), EU812849.1 (H6), EU812861.1 (H7), EU812869.1 (H8), EU812874.1 (H9), EU812898.1 (H10), EU812915.1 (H11), EU812927.1 (H12), EU812954.1 (H13), AF220662 (H14), AF289650 (H15), AF289649 (H16), GU143965 (H17), GU143986 (H18), EF379128 (H19); P. cynomolgi dbp1: AB617788.1 (Cambodia strain), JQ422035.1 (Berok strain), XM_004221494.1 (B strain); P. cynomolgi dbp2: AB617789.1 (Cambodia strain), JQ422036.1 (Berok strain), XM004220981.1 (B strain); P. knowlesi dbp: M90466.1 (alpha), M90694.1 (beta) and (M90695.1 gamma); P. fieldi dbp: AB617790.1; P. simiovale dbp: AB617791.1; and three haplotypes of P. simium isolates herein (H1, H2, H3). The tree was build using Maximum likelihood method with the Tamura and Nei model (TN93 model) in Mega 5.2. Numbers in the nodes indicate bootstrap values greater than 50.
Fig 2.
Three-dimensional structure of the PvDBPII dimer.
PvDBPII dimer (3RRC) showing the polymorphic sites in P. vivax (red) and P. simium (white). The three subdomains of the protein are shown in green (subdomain 1), orange (subdomain 2) and light green (subdomain 3). Residues important for the DARC interaction are shown in blue. 3-D structure visualized using PyMol. The structures correspond to a 180° rotation in the horizontal plan.
Table 1.
Single nucleotide polymorphisms (SNPs) in the ligand domain of the Duffy binding protein (DBPII)-encoding gene in seven isolates of Plasmodium simium.
Table 2.
Genetic diversity of P. simium DBPII compared to other Plasmodium DBPII.
Fig 3.
Schematic model of DARC showing polymorphic sites.
The 2-D model of DARC from Homo sapiens was constructed using TOPO2 software. Polymorphic sites in primates are shown in orange, purple (SNPs exclusive to the Cercopithecidae family), green (SNPs exclusive to the Platyrrhini parvorder) and blue (SNPs exclusive to the Hominoidea superfamily). Residues involved in direct binding to DARC are indicated (20–22 and 24–26) according to Batchelor et al. [53]. The arrow indicates Asp42Gly. Polymorphisms were annotated only until codon 255 (fragment available in our sequences).
Table 3.
Genetic diversity of DARC from Southern brown howler monkeys (Alouatta g. clamitans).
Fig 4.
Phylogenetic tree of DARC from primates.
Sequences of DARC from 47 primate species available from GenBank were aligned with the Alouatta g. clamitans DARC sequences described here. Clusters of parvorder: Platyrrhini and Catarrhini, and Families: Cercopithecidae, Hominidae, Hylobatidae, Pitheciidae, Atelidae and Cebidae are indicated. The numbers in the boxes correspond to the exclusive codons from each group (one letter amino acid and position).
Fig 5.
Interaction of Alouatta g. clamitans DARC and PvDBPII.
(A) Interaction between P. vivax DBPII expressed on the COS7 cell surface and DARC on the surface of A. clamitans erythrocytes (BL10 and BL34), representative of two experiments. Green fluorescence indicates transfected cells expressing GFP. (B) The negative control was performed using human DARC-negative erythrocytes. The cells were observed using conventional epifluorescence microscopy (×200). White arrows indicate the rosettes.
Table 4.
Characteristics of immune sera from monkeys used for the inhibition of the hDARC/PvDBPII interaction.