Disruption of the C-terminal region of EBA-175 in the Dd2/Nm clone of Plasmodium falciparum does not affect erythrocyte invasion

Mol Biochem Parasitol. 2000 Sep;110(1):135-46. doi: 10.1016/s0166-6851(00)00263-2.

Abstract

EBA-175 is a Plasmodium falciparum micronemal protein that binds to sialic acid in the context of the peptide backbone of glycophorin A and has been implicated in sialic acid-dependent invasion of erythrocytes. The existence of an alternative invasion pathway has been suggested by the finding that the P. falciparum clone Dd2/Nm can invade sialic acid-depleted erythrocytes. To study the role of EBA-175 in this alternative pathway, we have generated Dd2/Nm clones expressing a truncated form of EBA-175 that lacks region 6 and the cytoplasmic domain. The protein still appears to be localized to the apical end in the vicinity of the micronemes, suggesting that region 6 and the cytoplasmic domain are not involved in EBA-175 trafficking to the micronemes. In these genetically modified clones, the level of truncated EBA-175 protein expression was greatly reduced. EBA-175-disrupted clones displayed normal rates of invasion of untreated and enzyme-treated human and animal erythrocytes, suggesting a lack of involvement of EBA-175 in this alternative invasion pathway.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Antigens, Protozoan*
  • Blotting, Southern
  • Carrier Proteins / chemistry*
  • Carrier Proteins / genetics
  • Carrier Proteins / metabolism*
  • Cloning, Molecular
  • Erythrocytes / metabolism
  • Erythrocytes / parasitology*
  • Humans
  • Malaria, Falciparum / parasitology
  • Microscopy, Fluorescence
  • Molecular Sequence Data
  • N-Acetylneuraminic Acid / metabolism
  • Plasmids / genetics
  • Plasmodium falciparum / pathogenicity*
  • Precipitin Tests
  • Protozoan Proteins / chemistry*
  • Protozoan Proteins / genetics
  • Protozoan Proteins / metabolism*
  • Reverse Transcriptase Polymerase Chain Reaction
  • Sequence Deletion
  • Transformation, Genetic

Substances

  • Antigens, Protozoan
  • Carrier Proteins
  • Protozoan Proteins
  • erythrocyte-binding antigen 175, Plasmodium
  • N-Acetylneuraminic Acid