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

version 3 (curated until May 28, 2011)

The novel coccidian micronemal protein MIC11 undergoes proteolytic maturation by sequential cleavage to remove an internal propeptide.

Harper, J. M., Zhou, X. W., Pszenny, V., Kafsack, B. F., Carruthers, V. B. (2004 Aug, Int J Parasitol)

Host cell invasion is a key step in the life cycle of the intracellular parasite Toxoplasma gondii, the causative agent of toxoplasmosis. Attachment and invasion by this parasite is dependent on secretion of proteins from the micronemes, cigar-shaped organelles found in the apical end of the parasite. Although many of these proteins contain adhesive motifs suggestive of a role in parasite attachment, a growing subset of microneme proteins (MICs) do not possess adhesive sequences implying that they have alternative roles. We have identified a novel 16 kDa microneme protein, TgMIC11, that is conserved among several coccidian parasites. As it traffics through the secretory system, TgMIC11 is modified by two successive proteolytic events to remove an internal propeptide, resulting in the mature protein that consists of an alpha-chain and beta-chain tethered by a single disulfide bond. Dual staining immunofluorescence confirmed that TgMIC11 localises to the apical micronemes and, like other micronemal proteins, it is also secreted in a calcium dependent manner. This is the first microneme protein characterised to date in the phylum Apicomplexa that possesses this unique structure and undergoes maturation by removal of an internal propeptide.

PubMed: 15313131, full text

Localisation information

TGME49_077080 (MIC5) microneme TgMIC5 protein

Experimental localisation: microneme during intracellular tachyzoite
  • Species: Toxoplasma gondii
  • Quote inferring localisation: ""
  • Microscopy type: Light
  • Microscopy method: polyclonal antibody directly to protein
  • Strain: RH
  • Gene model mapping comments: inferred from another publication
  • Localisation record: microneme during intracellular tachyzoite

TGME49_014940 (M2AP, proTgM2AP) MIC2-associated protein M2AP

Experimental localisation: microneme during extracellular tachyzoite
  • Species: Toxoplasma gondii
  • Quote inferring localisation: ""
  • Microscopy type: Light
  • Microscopy method: polyclonal antibody directly to protein
  • Strain: RH
  • Gene model mapping comments: inferred from another publication
  • Localisation record: microneme during extracellular tachyzoite

TGME49_004530 (MIC11) microneme protein MIC11

Experimental localisation: microneme during tachyzoite
  • Species: Toxoplasma gondii
  • Quote inferring localisation: "Dual staining immunofluorescence confirmed that TgMIC11 localises to the apical micronemes"
  • Microscopy type: Light
  • Microscopy method: polyclonal antibody directly to protein
  • Strain: RH
  • Gene model mapping comments: Blast from AF539702, annotation matches
  • Localisation record: microneme during tachyzoite