Dynamic association of PfEMP1 and KAHRP in knobs mediates cytoadherence during Plasmodium invasion

Sci Rep. 2015 Mar 2:5:8617. doi: 10.1038/srep08617.

Abstract

Plasmodium falciparum infected erythrocytes display membrane knobs that are essential for their adherence to vascular endothelia and for prevention of clearance by the spleen. The knob associated histidine rich protein (KAHRP) is indispensable to knob formation and has been implicated in the recruitment and tethering of P. falciparum erythrocyte membrane protein-1 (PfEMP1) by binding to its cytoplasmic domain termed VARC. However, the precise mechanism of interaction between KAHRP and VARC is not very well understood. Here we report that both the proteins co-localize to membrane knobs of P. falciparum infected erythrocytes and have identified four positively charged linear sequence motifs of high intrinsic mobility on KAHRP that interact electrostatically with VARC in solution to form a fuzzy complex. The current study provides molecular insight into interaction between KAHRP and VARC in solution that takes place at membrane knobs.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Motifs
  • Cell Adhesion
  • Erythrocyte Membrane / metabolism*
  • Erythrocytes / metabolism
  • Erythrocytes / parasitology
  • Fluorescent Antibody Technique
  • Humans
  • Intrinsically Disordered Proteins / metabolism
  • Peptides / chemistry
  • Peptides / metabolism*
  • Plasmodium falciparum / physiology*
  • Protein Binding
  • Protein Structure, Tertiary
  • Protozoan Proteins / chemistry
  • Protozoan Proteins / metabolism*
  • Repetitive Sequences, Amino Acid
  • Solutions

Substances

  • Intrinsically Disordered Proteins
  • Peptides
  • Protozoan Proteins
  • Solutions
  • knob protein, Plasmodium falciparum