Laha Thewarach, Loukas Alex, Smyth Danielle J, Copeland Claudia S, Brindley Paul J
Department of Parasitology, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002, Thailand.
Int J Parasitol. 2004 Nov;34(12):1365-75. doi: 10.1016/j.ijpara.2004.08.007.
Inspection of the nucleotide sequence of bacterial artificial chromosome number 49_J_14 [Le Paslier, M.C., Pierce, R.J., Merlin, F., Hirai, H., Wu, W., Williams, D.L., Johnston, D., LoVerde, P.T., Le Paslier, D., 2000. Construction and characterization of a Schistosoma mansoni bacterial artificial chromosome library. Genomics 65, 87-94] from chromosome 1 of the genome of Schistosoma mansoni (GenBank ) revealed the likely presence of a proviral form of a novel schistosome retrotransposon. The novel element, which we named the fugitive, belonged to the mag-like family of the gypsy-Ty3 clade of long terminal repeat retrotransposons. It was closely related to the mag-like retrotransposon Gulliver from Schistosoma japonicum, but was dissimilar to several other long terminal repeat retrotransposons known from S. mansoni including Boudicca, Saci-1, Saci-2 and Saci-3. The full length fugitive element was 4811 bp constituted of a single read-through open reading frame of 4134 bp flanked at both ends by identical long terminal repeat sequences of 273 bp. The open reading frame encoded retroviral-like gag, with a distinctive double Cys-His motif, and pol polyprotein, with a pol domain order of protease, reverse transcriptase, RNaseH and integrase. Examination of schistosome transcriptome sequences in the public domain revealed that the fugitive was transcribed in at least six developmental stages of S. mansoni, while bioinformatics approaches and Southern hybridisation analysis indicated that as many as 2000 copies of the fugitive were interspersed throughout the schistosome genome.
对曼氏血吸虫(GenBank )基因组1号染色体上细菌人工染色体49_J_14的核苷酸序列进行检测[勒帕利耶,M.C.,皮尔斯,R.J.,梅林,F.,平井,H.,吴,W.,威廉姆斯,D.L.,约翰斯顿,D.,洛弗德,P.T.,勒帕利耶,D.,2000年。曼氏血吸虫细菌人工染色体文库的构建与表征。基因组学65,87 - 94],结果显示可能存在一种新型血吸虫逆转录转座子的前病毒形式。这种新型元件,我们将其命名为“逃亡者”,属于长末端重复逆转录转座子的吉普赛 - Ty3进化枝中类mag家族。它与日本血吸虫的类mag逆转录转座子格列佛密切相关,但与曼氏血吸虫已知的其他几种长末端重复逆转录转座子不同,包括布迪卡、萨西 - 1、萨西 - 2和萨西 - 3。全长的“逃亡者”元件为4811 bp,由一个4134 bp的单读通开放阅读框组成,两端侧翼是273 bp的相同长末端重复序列。该开放阅读框编码具有独特双半胱氨酸 - 组氨酸基序的逆转录病毒样gag蛋白,以及具有蛋白酶、逆转录酶、核糖核酸酶H和整合酶结构域顺序的pol多蛋白。对公共领域中血吸虫转录组序列的检测表明,“逃亡者”在曼氏血吸虫至少六个发育阶段都有转录,而生物信息学方法和Southern杂交分析表明,多达2000个“逃亡者”拷贝散布在整个血吸虫基因组中。