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

version 3 (curated until May 28, 2011)

A secreted serine-threonine kinase determines virulence in the eukaryotic pathogen Toxoplasma gondii.

Taylor, S., Barragan, A., Su, C., Fux, B., Fentress, S. J., Tang, K., Beatty, W. L., Hajj, H. E., Jerome, M., Behnke, M. S., White, M., Wootton, J. C., Sibley, L. D. (2006 Dec 15, Science)

Toxoplasma gondii strains differ dramatically in virulence despite being genetically very similar. Genetic mapping revealed two closely adjacent quantitative trait loci on parasite chromosome VIIa that control the extreme virulence of the type I lineage. Positional cloning identified the candidate virulence gene ROP18, a highly polymorphic serine-threonine kinase that was secreted into the host cell during parasite invasion. Transfection of the virulent ROP18 allele into a nonpathogenic type III strain increased growth and enhanced mortality by 4 to 5 logs. These attributes of ROP18 required kinase activity, which revealed that secretion of effectors is a major component of parasite virulence.

PubMed: 17170305, full text

Localisation information

TGME49_005250 (ROP18) Rhoptry kinase family protein ROP18

Experimental localisation: parasitophorous vacuole during early intracellular tachyzoite, cytoplasmic vesicle during early intracellular tachyzoite, rhoptry during late intracellular tachyzoite
  • Species: Toxoplasma gondii
  • Quote inferring localisation: "ROP18-I (green) was secreted into early PVs and into vesicles in the cytosol (arrows). In late PVs, ROP18-I accumulated in the rhoptries of mature daughter cells. Cryoimmuno–electron microscopy confirmed that ROP18 was found in rhoptries and released into the PV"
  • Microscopy type: Light, EM
  • Microscopy method: Ty tag
  • Strain: GT-1
  • Gene model mapping comments: Blast from EF092842.1
  • Localisation record: PV and cytosolic vesicles during early intracellular tachyzoite, rhoptries during late intracellular tachyzoite
  • Comment: Interesting virulence characterisitics

TGME49_109590 (ROP1) rhoptry protein, putative

Experimental localisation: rhoptry
  • Species: Toxoplasma gondii
  • Quote inferring localisation: "Ty epitope–tagged ROP18-I was found in early parasitophorous vacuoles (PVs), where it overlapped with the rhoptry marker ROP1"
  • Microscopy type: Light
  • Microscopy method: polyclonal antibody directly to protein
  • Strain: GT-1
  • Gene model mapping comments: inferred from another publication
  • Localisation record: rhoptries