ApiLoc - A database of published protein sub-cellular localisation in Apicomplexa

version 3 (curated until May 28, 2011)

The Plasmodium vivax homologues of merozoite surface proteins 4 and 5 from Plasmodium falciparum are expressed at different locations in the merozoite.

Black, C. G., Barnwell, J. W., Huber, C. S., Galinski, M. R., Coppel, R. L. (2002 Apr 9, Mol Biochem Parasitol)

Merozoite surface proteins of Plasmodium falciparum are one major group of antigens currently being investigated and tested as malaria vaccine candidates. Two recently described P. falciparum merozoite surface antigens, MSP4 and MSP5, are GPI-anchored proteins that each contain a single EGF-like domain and appear to have arisen by an ancient gene duplication event. The genes are found in tandem on chromosome 2 of P. falciparum and the syntenic region of the genome was identified in the rodent malarias P. chabaudi, P. yoelii and P. berghei. In these species, there is only a single gene, designated MSP4/5 encoding a single EGF-like domain similar to the EGF-like domain in both PfMSP4 and PfMSP5. Immunization of mice with PyMSP4/5 provides mice with high levels of protection against lethal challenge with blood stage P. yoelii. In this study, we show that in P. vivax, which is quite phylogenetically distant from P. falciparum, both MSP4 and MSP5 homologues can be found with their relative arrangements with respect to the surrounding genes mostly preserved. However, the gene for MSP2, found between MSP5 and adenylosuccinate lyase (ASL) in P. falciparum, is absent from P. vivax. The PvMSP4 and PvMSP5 genes have a two-exon structure and encode proteins with potential signal and GPI anchor sequences and a single EGF-like domain near the carboxyl-terminus. Rabbit antisera raised against purified recombinant proteins show that each of the antisera react with distinct proteins of 62 kDa for PvMSP4 and 86 kDa for PvMSP5 in parasite lysates. Indirect immunofluorescence assays (IFA) localized PvMSP4 over the entire surface of P. vivax merozoites, as expected, whereas, the MSP5 homologue was found to be associated with an apical organellar location consistent with micronemes or over the polar prominence.

PubMed: 11897127, full text

Localisation information

PVX_003775 (MSP4) merozoite surface protein 4, putative

Experimental localisation: surface during mature schizont
  • Species: Plasmodium vivax
  • Quote inferring localisation: "Indirect IFA analysis of thin smears of mature and segmented P. vivax schizonts localized expression of PvMSP4 to the merozoite surface as was to be expected based on previous results with antibodies to PfMSP4."
  • Microscopy type: Light
  • Microscopy method: polyclonal antibody
  • Strain: Plasmodium vivax (Belem
  • Gene model mapping comments: Blast from AF403475, annotation matches
  • Localisation record: surface during mature schizont
  • Comment: strain information not found

PVX_003770 (MSP5) merozoite surface protein 5

Experimental localisation: apical during merozoite, not surface during merozoite
  • Species: Plasmodium vivax
  • Quote inferring localisation: "Surprisingly, the pattern of fluorescent reactivity with antisera to PvMSP5 was not consistent with the bunch of grapes surface rim pattern typically seen with antibodies to MSP1, MSP2, MSP3, MSP4, or that reported for P. falciparum MSP5. Instead, the pattern seen consistently with either rabbit (Fig. 4B and E) or mouse (not shown) PvMSP5 antisera was that of a localization exhibiting as a single large dot or spot of fluorescence at the apical end of the merozoite."
  • Microscopy type: Light
  • Microscopy method: polyclonal antibody
  • Strain: Plasmodium vivax (Belem
  • Gene model mapping comments: Blast from AF403476, annotation matches
  • Localisation record: apical and not surface during merozoite
  • Comment: strain information not found

PVX_110810 (DBP) Duffy receptor precursor

Experimental localisation: microneme during mature schizont
  • Species: Plasmodium vivax
  • Quote inferring localisation: "In an attempt at finer discrimination of a potential organellar location, we performed two-color IFA using rabbit anti-PvMSP5, monoclonal antibody (mAb) 1C10 against the P. vivax duffy binding protein (PvDBP) (Fig. 4C), which is located in micronemes, and mAb 4E1 ( Fig. 4F), which recognizes a 105 kDa antigen in the paired rhoptry organelles."
  • Microscopy type: Light
  • Microscopy method: monoclonal antibody (mAb1C10)
  • Strain:
  • Gene model mapping comments: Annotation only
  • Localisation record: microneme during mature schizont
  • Comment: strain information not found