Evidence for the Importance of Genetic Structuring to the Structural and Functional Specialization of the Plasmodium Falciparum Var Gene Family

Mol Microbiol. 2003 Dec;50(5):1527-38. doi: 10.1046/j.1365-2958.2003.03814.x.

Abstract

The var gene family encodes Plasmodium falciparum erythrocyte membrane 1 (PfEMP1) proteins that act as virulence factors responsible for both antigenic variation and cytoadherence of infected erythrocytes. These proteins orchestrate infected erythrocyte sequestration from blood circulation and contribute to adhesion-based complications of P. falciparum malaria infections. For this study, we analysed the genetic organization and strain structure of var genes and present evidence for three separately evolving groups that have, in part, functionally diverged and differ between subtelomeric and central chromosomal locations. Our analyses suggest that a recombination hierarchy limits reassortment between groups and may explain why some var genes are unusually conserved between parasite strains. This recombination hierarchy, coupled with binding and immune selection, shapes the variant antigen repertoire and has structural, functional and evolutionary consequences for the PfEMP1 protein family that are directly relevant to malaria pathogenesis.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • CD36 Antigens / metabolism
  • Cell Adhesion
  • Erythrocytes / parasitology
  • Evolution, Molecular
  • Genome, Protozoan*
  • Molecular Sequence Data
  • Multigene Family
  • Phylogeny*
  • Plasmodium falciparum / classification
  • Plasmodium falciparum / genetics*
  • Plasmodium falciparum / metabolism
  • Protozoan Proteins* / chemistry
  • Protozoan Proteins* / genetics
  • Protozoan Proteins* / metabolism
  • Recombination, Genetic*
  • Sequence Analysis, DNA
  • Structure-Activity Relationship
  • Telomere / genetics*

Substances

  • CD36 Antigens
  • Protozoan Proteins
  • erythrocyte membrane protein 1, Plasmodium falciparum