Carreira M A, Tibbetts R S, Olson C L, Schuster C, Renz M, Engman D M, Goldenberg S
Departamento de Bioquímica e Biologia Molecular, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil.
FEMS Microbiol Lett. 1998 Sep 1;166(1):141-6. doi: 10.1111/j.1574-6968.1998.tb13195.x.
A full length cDNA encoding a novel Trypanosoma cruzi DnaJ protein was cloned and characterized. The 324 amino acid protein encoded by the cDNA (TcDJ1) displays a characteristics J-domain, but lacks the Gly-Phe and zinc finger regions present in some other DnaJ proteins. Relative to four other T. cruzi DnaJ proteins, TcDJ1 has an amino terminal extension containing basic and hydroxylated resides characteristic of mitochondrial import peptides. A T. cruzi transfectant expressing epitope-tagged TcDJ1 was generated and subcellular fractions were produced. Western blot analysis revealed that the protein has a molecular mass of 29 kDa and is found in the mitochondrial fraction. The expression of TcDJ1 is developmentally regulated since the levels of both mRNA and protein are much higher in epimastigotes (replicative form) than in metacyclic trypomastigotes (infective form). Thus it may participate in mitochondrial biosynthetic processes in this organism.
克隆并鉴定了一个编码新型克氏锥虫DnaJ蛋白的全长cDNA。该cDNA编码的324个氨基酸的蛋白（TcDJ1）具有典型的J结构域，但缺少其他一些DnaJ蛋白中存在的甘氨酸-苯丙氨酸和锌指区域。相对于其他四种克氏锥虫DnaJ蛋白，TcDJ1具有一个氨基末端延伸区，含有线粒体导入肽特有的碱性和羟基化残基。构建了表达表位标记的TcDJ1的克氏锥虫转染体，并制备了亚细胞组分。蛋白质印迹分析表明，该蛋白的分子量为29 kDa，存在于线粒体组分中。TcDJ1的表达受发育调控，因为其mRNA和蛋白水平在无鞭毛体（增殖形式）中比在循环后期锥鞭毛体（感染形式）中高得多。因此，它可能参与该生物体的线粒体生物合成过程。
