A novel phosphatidylinositol-phospholipase C of Trypanosoma cruzi that is lipid modified and activated during trypomastigote to amastigote differentiation
A novel phosphatidylinositol-phospholipase C of Trypanosoma cruzi that is lipid modified and activated during trypomastigote to amastigote differentiation
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DOI：
10.1074/jbc.275.9.6428
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发表时间：
2000-03-03
影响因子：
4.8
通讯作者：
Moreno, SNJ
中科院分区：
文献类型：
--
作者：
Furuya, T;Kashuba, C;Moreno, SNJ
磷脂酰肌醇（PI）特异性磷脂酶C基因克隆了克氏锥虫TcPI-PLC基因，并进行了序列测定，在大肠杆菌中表达，TcPI-PLC基因在寄生虫的上鞭毛体和无鞭毛体阶段以高水平表达，并且在锥鞭毛体分化为无鞭毛体的过程中诱导其表达，其中TcPI-PLC与质膜结合并增加其催化活性。与迄今为止描述的其他PI-PLC相比，TcPI-PLC的推导的氨基酸序列揭示了一些独特的特征，例如在其氨基末端的N-肉豆蔻酰化共有序列，缺乏明显的pleckstrin同源结构域和催化X和Y结构域之间的高度带电的接头区域，TcPI-PLC在体内被脂质修饰，如用[H-3]肉豆蔻酸酯和[H-3]棕榈酸酯的代谢标记和免疫沉淀蛋白的脂肪酸分析所证明的，并且可以构成新的PI-PLC组的第一个实例。
The phosphoinositide (PI)-specific phospholipase C gene (TcPI-PLC) of the protozoan parasite Trypanosoma cruzi was cloned, sequenced, expressed in Escherichia coli, and the protein product (TcPI-PLC) was shown to have enzymatic characteristics similar to those of mammalian delta-type PI-PLCs, The TcPI-PLC gene is expressed at high levels in the epimastigote and amastigote stages of the parasite, and its expression is induced during the differentiation of trypomastigotes into amastigotes, where TcPI-PLC associates with the plasma membrane and increases its catalytic activity. In contrast to other PI-PLCs described so far, the deduced amino acid sequence of TcPI-PLC revealed some unique features such as an N-myristoylation consensus sequence at its aminoterminal end, lack of an apparent pleckstrin homology domain and a highly charged linker region between the catalytic X and Y domains, TcPI-PLC is lipid modified in vivo, as demonstrated by metabolic labeling with [H-3]myristate and [H-3]palmitate and fatty acid analysis of the immunoprecipitated protein, and may constitute the first example of a new group of PI-PLCs.