The toxoplasma micronemal protein MIC4 is an adhesin composed of six conserved apple domains.
The initial stage of invasion by apicomplexan parasites involves the exocytosis of the micronemes-containing molecules that contribute to host cell attachment and penetration. MIC4 was previously described as a protein secreted by Toxoplasma gondii tachyzoites upon stimulation of micronemes exocytos...
Main Authors: | , , , , , , , , |
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Format: | Journal article |
Language: | English |
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2001
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author | Brecht, S Carruthers, V Ferguson, D Giddings, O Wang, G Jakle, U Harper, J Sibley, L Soldati, D |
author_facet | Brecht, S Carruthers, V Ferguson, D Giddings, O Wang, G Jakle, U Harper, J Sibley, L Soldati, D |
author_sort | Brecht, S |
collection | OXFORD |
description | The initial stage of invasion by apicomplexan parasites involves the exocytosis of the micronemes-containing molecules that contribute to host cell attachment and penetration. MIC4 was previously described as a protein secreted by Toxoplasma gondii tachyzoites upon stimulation of micronemes exocytosis. We have microsequenced the mature protein, purified after discharge from micronemes and cloned the corresponding gene. The deduced amino acid sequence of MIC4 predicts a 61-kDa protein that contains 6 conserved apple domains. Apple domains are composed of six spacely conserved cysteine residues which form disulfide bridges and are also present in micronemal proteins from two closely related apicomplexan parasites, Sarcocystis muris and Eimeria species, and several mammalian serum proteins, including kallikrein. Here we show that MIC4 localizes in the micronemes of all the invasive forms of T. gondii, tachyzoites, bradyzoites, sporozoites, and merozoites. The protein is proteolytically processed both at the N and the C terminus only upon release from the organelle. MIC4 binds efficiently to host cells, and the adhesive motif maps in the most C-terminal apple domain. |
first_indexed | 2024-03-07T05:07:17Z |
format | Journal article |
id | oxford-uuid:da5a64d5-1347-4df0-b365-675a3e891140 |
institution | University of Oxford |
language | English |
last_indexed | 2024-03-07T05:07:17Z |
publishDate | 2001 |
record_format | dspace |
spelling | oxford-uuid:da5a64d5-1347-4df0-b365-675a3e8911402022-03-27T09:02:42ZThe toxoplasma micronemal protein MIC4 is an adhesin composed of six conserved apple domains.Journal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:da5a64d5-1347-4df0-b365-675a3e891140EnglishSymplectic Elements at Oxford2001Brecht, SCarruthers, VFerguson, DGiddings, OWang, GJakle, UHarper, JSibley, LSoldati, DThe initial stage of invasion by apicomplexan parasites involves the exocytosis of the micronemes-containing molecules that contribute to host cell attachment and penetration. MIC4 was previously described as a protein secreted by Toxoplasma gondii tachyzoites upon stimulation of micronemes exocytosis. We have microsequenced the mature protein, purified after discharge from micronemes and cloned the corresponding gene. The deduced amino acid sequence of MIC4 predicts a 61-kDa protein that contains 6 conserved apple domains. Apple domains are composed of six spacely conserved cysteine residues which form disulfide bridges and are also present in micronemal proteins from two closely related apicomplexan parasites, Sarcocystis muris and Eimeria species, and several mammalian serum proteins, including kallikrein. Here we show that MIC4 localizes in the micronemes of all the invasive forms of T. gondii, tachyzoites, bradyzoites, sporozoites, and merozoites. The protein is proteolytically processed both at the N and the C terminus only upon release from the organelle. MIC4 binds efficiently to host cells, and the adhesive motif maps in the most C-terminal apple domain. |
spellingShingle | Brecht, S Carruthers, V Ferguson, D Giddings, O Wang, G Jakle, U Harper, J Sibley, L Soldati, D The toxoplasma micronemal protein MIC4 is an adhesin composed of six conserved apple domains. |
title | The toxoplasma micronemal protein MIC4 is an adhesin composed of six conserved apple domains. |
title_full | The toxoplasma micronemal protein MIC4 is an adhesin composed of six conserved apple domains. |
title_fullStr | The toxoplasma micronemal protein MIC4 is an adhesin composed of six conserved apple domains. |
title_full_unstemmed | The toxoplasma micronemal protein MIC4 is an adhesin composed of six conserved apple domains. |
title_short | The toxoplasma micronemal protein MIC4 is an adhesin composed of six conserved apple domains. |
title_sort | toxoplasma micronemal protein mic4 is an adhesin composed of six conserved apple domains |
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