Toxoplasma gondii expresses an unusual cathepsin L-like protease that occupies a unique intermediate apical compartment

FABIOLA PARUSSINI; GOSALIA DAVAL; SCOTT L. DIAMOND; MATTHEW BOGYO; ISABELLE COPPENS; VERN B. CARRUTHERS

Wood Hole

Congreso; Annual Molecular Parasitology Meeting; 2005

Micronemes, rhoptries, and dense granules are sequentially released during cell invasion by apicomplexan parasites such as Toxoplasma gondii. A subset of invasion proteins undergo proteolytic maturation during their transport to the secretory organelles, and further processing on the parasite surface, or both. It is becoming clear that the proteolytic processing of microneme (MIC) proteins is important in the function of these proteins by stabilizing protein complex formation, facilitating trafficking to secretory organelles, or regulating enzymatic or adhesive activity. The use of general protease inhibitors have revealed that serine and cysteine proteases play critical roles in different steps of Toxoplasma host cell invasion. The goal of this work is to identify the protease(s) involved in the proteolytic maturation of MIC proteins. We propose that the Toxoplasma gondii cathepsin L-like protease (TgCPL)  is a maturase for several MIC proteins including proM2AP