Molecular signals in the trafficking of Toxoplasma gondii protein MIC3 to the micronemes
Molecular signals in the trafficking of Toxoplasma gondii protein MIC3 to the micronemes
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DOI：
10.1128/ec.00413-07
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发表时间：
2008-06-01
期刊：
影响因子：
--
通讯作者：
Lebrun, Maryse
中科院分区：
文献类型：
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作者：
El Hajj, Hiba;Papoin, Julien;Lebrun, Maryse
弓形虫具有复杂的分泌器，包括三种不同的胞外细胞器，分别称为微丝、棒状体和致密颗粒。我们已经剖析了靶向微线体蛋白MIC3的要求，MIC3是T.弓形虫感染我们已经表明，MIC3是在后高尔基体隔室处理，MIC3前肽和表皮生长因子（EGF）模块包含微线靶向信息。微线递送的最低要求由前肽加上三个EGF结构域中的任何一个限定。我们已经证明，裂解的前肽，MIC3的二聚化，和几丁质结合样序列，这是至关重要的宿主细胞的结合和毒力，是不适合适当的靶向。最后，我们已经表明，MIC3的一部分被扣留在分泌途径中的细胞周期依赖性的方式。
The protozoan parasite Toxoplasma gondii is equipped with a sophisticated secretory apparatus, including three distinct exocytic organelles, named micronemes, rhoptries, and dense granules. We have dissected the requirements for targeting the microneme protein MIC3, a key component of T. gondii infection. We have shown that MIC3 is processed in a post-Golgi compartment and that the MIC3 propeptide and epidermal growth factor (EGF) modules contain microneme-targeting information. The minimal requirement for microneme delivery is defined by the propeptide plus any one of the three EGF domains. We have demonstrated that the cleavage of the propeptide, the dimerization of MIC3, and the chitin binding-like sequence, which are crucial for host cell binding and virulence, are dispensable for proper targeting. Finally, we have shown that part of MIC3 is withheld in the secretory pathway in a cell cycle-dependent manner.