Characterization of RAB-like4, the first identified RAB-like protein from Trypanosoma cruzi with GTPase activity.
Characterization of RAB-like4, the first identified RAB-like protein from Trypanosoma cruzi with GTPase activity.
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DOI：
10.1016/j.bbrc.2005.05.183
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发表时间：
2005-08
影响因子：
3.1
通讯作者：
F. Ramos;J. Araripe;T. Urményi;Rosane Silva;N. L. Cunha E Silva;Carlos Frederico Leite Fontes;J. F. da Silveira;E. Rondinelli
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文献类型：
--
作者：
F. Ramos;J. Araripe;T. Urményi;Rosane Silva;N. L. Cunha E Silva;Carlos Frederico Leite Fontes;J. F. da Silveira;E. Rondinelli
RAB蛋白属于RAS超家族，调节真核细胞的胞外和内吞途径，控制囊泡对接和融合。在寄生虫中发现的RAB蛋白很少。细胞区室分子标记对研究恰加斯病病原克氏锥虫的蛋白质转运具有重要意义。在这项工作中，我们描述了TcRABL4的特征，这是在克氏体中发现的第一个rabb样基因。：)，以单拷贝基因的形式存在。TcRABL4包含所有五个公认的RAB基序，但在C端缺乏半胱氨酸残基，这是异戊二烯化所必需的，这是这些蛋白质膜结合的绝对先决条件。TcRABL4是一种功能性的GTP酶，能够结合和水解GTP，其基因在附原体中转录为一个1.2kb的mRNA。TcRABL4似乎在寄生虫的三种细胞形式中受到不同的调节，并且与其他RAB蛋白不同，该蛋白与膜无关。TcRABL4可能是一个新的小GTPases家族的成员。
RAB proteins, which belong to the RAS superfamily, regulate exocytic and endocytic pathways of eukaryotic cells, controlling vesicle docking and fusion. Few RAB proteins have been identified in parasites. Molecular markers for cellular compartments are important to studies concerning about the protein traffic in Trypanosoma cruzi, the causal agent of Chagas disease. In this work, we describe the characterization of TcRABL4, the first RAB-like gene identified in T. cruzi (GenBank Accession No.: ), present as a single-copy gene. TcRABL4 contains all five consensus RAB motifs but lacks cysteine residues at the C terminus, which are essential to isoprenylation, an absolute prerequisite for membrane association of these proteins. TcRABL4 is a functional GTPase that is able to bind and hydrolyze GTP, and its gene is transcribed as a single 1.2kb mRNA in epimastigotes. TcRABL4 appears to be differentially regulated in the three cell forms of the parasite, and the protein is not associated to membranes, unlike other RAB proteins. It is possible that TcRABL4 may be a member of a novel family of small GTPases.