For COVID-19 vaccine updates, please review our information guide. For patient eligibility and scheduling availability, please visit VaccineTogetherNY.org.

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

TitleThe novel coccidian micronemal protein MIC11 undergoes proteolytic maturation by sequential cleavage to remove an internal propeptide.
Publication TypeJournal Article
Year of Publication2004
AuthorsHarper JM, Zhou XW, Pszenny V, Kafsack BFC, Carruthers VB
JournalInt J Parasitol
Volume34
Issue9
Pagination1047-58
Date Published2004 Aug
ISSN0020-7519
KeywordsAmino Acid Sequence, Animals, Calcium, Cell Adhesion Molecules, Chelating Agents, DNA, Complementary, DNA, Protozoan, Egtazic Acid, Electrophoresis, Gel, Two-Dimensional, Female, Mass Spectrometry, Mice, Mice, Inbred BALB C, Molecular Sequence Data, Protozoan Proteins, Sequence Analysis, DNA, Toxoplasma
Abstract

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.

DOI10.1016/j.ijpara.2004.05.006
Alternate JournalInt J Parasitol
PubMed ID15313131
Grant List1S10-RR14702 / RR / NCRR NIH HHS / United States
AI46675 / AI / NIAID NIH HHS / United States

Weill Cornell Medicine Microbiology and Immunology 1300 York Avenue, Box 62 New York, NY 10065 Phone: (212) 746-6505 Fax: (212) 746-8587