Targeted deletion of MIC5 enhances trimming proteolysis of Toxoplasma invasion proteins

被引:17
作者
Brydges, Susannah D.
Zhou, Xing Wang
Huynh, My-Hang
Harper, Jill M.
Mital, Jeffrey
Adjogble, Koku D. Z.
Daeubener, Walter
Ward, Gary E.
Carruthers, Vern B.
机构
[1] Johns Hopkins Bloomberg Sch Publ Hlth, Harry Feinstone Dept Mol Microbiol & Immunol, Baltimore, MD 21205 USA
[2] Univ Vermont, Dept Microbiol & Mol Genet, Burlington, VT 05405 USA
[3] Inst Med Microbiol & Hosp Hyg, D-40225 Dusseldorf, Germany
关键词
D O I
10.1128/EC.00163-06
中图分类号
Q93 [微生物学];
学科分类号
071005 ; 100705 ;
摘要
Limited proteolysis of proteins transiently expressed on the surface of the opportunistic pathogen Toxoplasma gondii accompanies cell invasion and facilitates parasite migration across cell barriers during infection. However, little is known about what factors influence this specialized proteolysis or how these proteolytic events are regulated. Here we show that genetic ablation of the micronemal protein MIC5 enhances the normal proteolytic processing of several micronemal proteins secreted by Toxoplasma tachyzoites. Restoring MIC5 expression by genetic complementation reversed this phenotype, as did treatment with the protease inhibitor ALLN, which was previously shown to block the activity of a hypothetical parasite surface protease called MPP2. We show that, despite its lack of obvious membrane association signals, MIC5 occupies the parasite surface during invasion in the vicinity of the proteins affected by enhanced processing. Proteolysis of other secretory proteins, including GRA1, was also enhanced in MIC5 knockout parasites, indicating that the phenotype is not strictly limited to proteins derived from micronemes. Together, our findings suggest that MIC5 either directly regulates MPP2 activity or it influences MPP2's ability to access substrate cleavage sites on the parasite surface.
引用
收藏
页码:2174 / 2183
页数:10
相关论文
共 48 条
[21]  
2-7
[22]   The Toxoplasma homolog of Plasmodium apical membrane antigen-1 (AMA-1) is a microneme protein secreted in response to elevated intracellular calcium levels [J].
Donahue, CG ;
Carruthers, VB ;
Gilk, SD ;
Ward, GE .
MOLECULAR AND BIOCHEMICAL PARASITOLOGY, 2000, 111 (01) :15-30
[23]   Insertional tagging, cloning, and expression of the Toxoplasma gondii hypoxanthine-xanthine-guanine phosphoribosyltransferase gene - Use as a selectable marker for stable transformation [J].
Donald, RGK ;
Carter, D ;
Ullman, B ;
Roos, DS .
JOURNAL OF BIOLOGICAL CHEMISTRY, 1996, 271 (24) :14010-14019
[24]   Apicomplexan rhomboids have a potential role in microneme protein cleavage during host cell invasion [J].
Dowse, TJ ;
Pascall, JC ;
Brown, KD ;
Soldati, D .
INTERNATIONAL JOURNAL FOR PARASITOLOGY, 2005, 35 (07) :747-756
[25]   EFFECTS OF EXTRACELLULAR POTASSIUM ON ACID RELEASE AND MOTILITY INITIATION IN TOXOPLASMA-GONDII [J].
ENDO, T ;
TOKUDA, H ;
YAGITA, K ;
KOYAMA, T .
JOURNAL OF PROTOZOOLOGY, 1987, 34 (03) :291-295
[26]   CONFORMATIONAL SPECIFICITY OF CHYMOTRYPSIN TOWARD PROLINE-CONTAINING SUBSTRATES [J].
FISCHER, G ;
BANG, H ;
BERGER, E ;
SCHELLENBERGER, A .
BIOCHIMICA ET BIOPHYSICA ACTA, 1984, 791 (01) :87-97
[27]   The MIC1 microneme protein of Toxoplasma gondii contains a duplicated receptor-like domain and binds to host cell surface [J].
Fourmaux, MN ;
Achbarou, A ;
MercereauPuijalon, O ;
Biderre, C ;
Briche, I ;
Loyens, A ;
OdbergFerragut, C ;
Camus, D ;
Dubremetz, JF .
MOLECULAR AND BIOCHEMICAL PARASITOLOGY, 1996, 83 (02) :201-210
[28]   The microneme protein MIC3 of Toxoplasma gondii is a secretory adhesin that binds to both the surface of the host cells and the surface of the parasite [J].
Garcia-Réguet, N ;
Lebrun, M ;
Fourmaux, MN ;
Mercereau-Puijalon, O ;
Mann, T ;
Beckers, CJM ;
Samyn, B ;
Van Beeumen, J ;
Bout, D ;
Dubremetz, JF .
CELLULAR MICROBIOLOGY, 2000, 2 (04) :353-364
[29]   Toxoplasma gondii:: Molecular cloning and characterization of a novel 18-kDa secretory antigen, TSMIC10 [J].
Hoff, EF ;
Cook, SH ;
Sherman, GD ;
Harper, JM ;
Ferguson, DJP ;
Dubremetz, JF ;
Carruthers, VB .
EXPERIMENTAL PARASITOLOGY, 2001, 97 (02) :77-88
[30]   Trans-genera reconstitution and complementation of an adhesion complex in Toxoplasma gondii [J].
Huynh, MH ;
Opitz, C ;
Kwok, LY ;
Tomley, FM ;
Carruthers, VB ;
Soldati, D .
CELLULAR MICROBIOLOGY, 2004, 6 (08) :771-782