Ankyrin-1 Gene Exhibits Allelic Heterogeneity in Conferring Protection Against Malaria

G3 (Bethesda). 2017 Sep 7;7(9):3133-3144. doi: 10.1534/g3.117.300079.

Abstract

Allelic heterogeneity is a common phenomenon where a gene exhibits a different phenotype depending on the nature of its genetic mutations. In the context of genes affecting malaria susceptibility, it allowed us to explore and understand the intricate host-parasite interactions during malaria infections. In this study, we described a gene encoding erythrocytic ankyrin-1 (Ank-1) which exhibits allelic-dependent heterogeneous phenotypes during malaria infections. We conducted an ENU mutagenesis screen on mice and identified two Ank-1 mutations, one resulting in an amino acid substitution (MRI95845), and the other a truncated Ank-1 protein (MRI96570). Both mutations caused hereditary spherocytosis-like phenotypes and confer differing protection against Plasmodium chabaudi infections. Upon further examination, the Ank-1(MRI96570) mutation was found to inhibit intraerythrocytic parasite maturation, whereas Ank-1(MRI95845) caused increased bystander erythrocyte clearance during infection. This is the first description of allelic heterogeneity in ankyrin-1 from the direct comparison between two Ank-1 mutations. Despite the lack of direct evidence from population studies, this data further supported the protective roles of ankyrin-1 mutations in conferring malaria protection. This study also emphasized the importance of such phenomena in achieving a better understanding of host-parasite interactions, which could be the basis of future studies.

Keywords: allelic heterogeneity; ankyrin-1; erythrocyte cytoskeleton; malaria.

MeSH terms

  • Alleles*
  • Animals
  • Ankyrins / genetics*
  • Disease Models, Animal
  • Disease Resistance / genetics
  • Erythrocytes / metabolism
  • Erythrocytes / parasitology
  • Erythrocytes / pathology
  • Erythrocytes / ultrastructure
  • Female
  • Genetic Heterogeneity*
  • Genetic Predisposition to Disease*
  • Host-Parasite Interactions / genetics*
  • Malaria / blood
  • Malaria / genetics*
  • Malaria / parasitology
  • Malaria / pathology
  • Male
  • Mice
  • Mutation
  • Osmotic Fragility / genetics
  • Phenotype
  • Spherocytosis, Hereditary / genetics
  • Spherocytosis, Hereditary / pathology
  • Whole Genome Sequencing

Substances

  • Ankyrins