Structural Insights Into PfARO and Characterization of its Interaction With PfAIP

J Mol Biol. 2020 Feb 14;432(4):878-896. doi: 10.1016/j.jmb.2019.12.024. Epub 2019 Dec 23.

Abstract

Apicomplexan parasites contain rhoptries, which are specialized secretory organelles that coordinate host cell invasion. During the process of invasion, rhoptries secrete their contents to facilitate interaction with, and entry into, the host cell. Here, we report the crystal structure of the rhoptry protein Armadillo Repeats-Only (ARO) from the human malaria parasite, Plasmodium falciparum (PfARO). The structure of PfARO comprises five tandem Armadillo-like (ARM) repeats, with adjacent ARM repeats stacked in a head-to-tail orientation resulting in PfARO adopting an elongated curved shape. Interestingly, the concave face of PfARO contains two distinct patches of highly conserved residues that appear to play an important role in protein-protein interaction. We functionally characterized the P. falciparum homolog of ARO interacting protein (PfAIP) and demonstrate that it localizes to the rhoptries. We show that conditional mislocalization of PfAIP leads to deficient red blood cell invasion. Guided by the structure, we identified mutations of PfARO that lead to mislocalization of PfAIP. Using proximity-based biotinylation we probe into PfAIP interacting proteins.

Keywords: BioID; armadillo proteins; host cell invasion; malaria; plasmodium.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Armadillo Domain Proteins / genetics
  • Armadillo Domain Proteins / metabolism
  • Humans
  • Malaria / physiopathology
  • Molecular Sequence Data
  • Mutagenesis / genetics
  • Mutagenesis / physiology
  • Mutation
  • Parasitemia / parasitology
  • Phylogeny
  • Plasmodium falciparum / genetics
  • Plasmodium falciparum / metabolism*
  • Plasmodium falciparum / pathogenicity*
  • Protein Transport / genetics
  • Protein Transport / physiology
  • Protozoan Proteins / genetics
  • Protozoan Proteins / metabolism*

Substances

  • Armadillo Domain Proteins
  • Protozoan Proteins

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