Plasmodium vivax Cysteine-Rich Protective Antigen Polymorphism at Exon-1 Shows Recombination and Signatures of Balancing Selection.
Genes (Basel)
; 12(1)2020 12 28.
Article
em En
| MEDLINE
| ID: mdl-33379267
Plasmodium vivax Cysteine-Rich Protective Antigen (CyRPA) is a merozoite protein participating in the parasite invasion of human reticulocytes. During natural P. vivax infection, antibody responses against PvCyRPA have been detected. In children, low anti-CyRPA antibody titers correlated with clinical protection, which suggests this protein as a potential vaccine candidate. This work analyzed the genetic and amino acid diversity of pvcyrpa in Mexican and global parasites. Consensus coding sequences of pvcyrpa were obtained from seven isolates. Other sequences were extracted from a repository. Maximum likelihood phylogenetic trees, genetic diversity parameters, linkage disequilibrium (LD), and neutrality tests were analyzed, and the potential amino acid polymorphism participation in B-cell epitopes was investigated. In 22 sequences from Southern Mexico, two synonymous and 21 nonsynonymous mutations defined nine private haplotypes. These parasites had the highest LD-R2 index and the lowest nucleotide diversity compared to isolates from South America or Asia. The nucleotide diversity and Tajima's D values varied across the coding gene. The exon-1 sequence had greater diversity and Rm values than those of exon-2. Exon-1 had significant positive values for Tajima's D, ß-α values, and for the Z (HA: dN > dS) and MK tests. These patterns were similar for parasites of different origin. The polymorphic amino acid residues at PvCyRPA resembled the conformational B-cell peptides reported in PfCyRPA. Diversity at pvcyrpa exon-1 is caused by mutation and recombination. This seems to be maintained by balancing selection, likely due to selective immune pressure, all of which merit further study.
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Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Plasmodium vivax
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Recombinação Genética
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Seleção Genética
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Proteínas de Protozoários
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Antígenos de Protozoários
Limite:
Humans
Idioma:
En
Revista:
Genes (Basel)
Ano de publicação:
2020
Tipo de documento:
Article
País de afiliação:
México
País de publicação:
Suíça