Aguilar-Díaz Hugo, Bobes Raúl J, Carrero Julio C, Camacho-Carranza Rafael, Cervantes Claudia, Cevallos Miguel A, Dávila Guillermo, Rodríguez-Dorantes Mauricio, Escobedo Galileo, Fernández José Luis, Fragoso Gladis, Gaytán Paul, Garciarubio Alejandro, González Victor M, González Lorena, José Marco V, Jiménez Lucía, Laclette Juan P, Landa Abraham, Larralde Carlos, Morales-Montor Jorge, Morett Enrique, Ostoa-Saloma Pedro, Sciutto Edda, Santamaría Rosa I, Soberón Xavier, de la Torre Patricia, Valdés Víctor, Yánez Jorge
Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Mexico.
Parasitol Int. 2006;55 Suppl:S127-30. doi: 10.1016/j.parint.2005.11.020. Epub 2005 Dec 6.
We have constituted a consortium of key laboratories at the National Autonomous University of Mexico to carry out a genomic project for Taenia solium. This project will provide powerful resources for the study of taeniasis/cysticercosis, and, in conjunction with the Echinococcus granulosus and Echinococcus multilocularis genome project of expressed sequence tags (ESTs), will mark the advent of genomics for cestode parasites. Our project is planned in two consecutive stages. The first stage is being carried out to determine some basic parameters of the T. solium genome. Afterwards, we will evaluate the best strategy for the second stage, a full blown genome project. We have estimated the T. solium genome size by two different approaches: cytofluorometry on isolated cyton nuclei, as well as a probabilistic calculation based on approximately 2000 sequenced genomic clones, approximately 3000 ESTs, resulting in size estimates of 270 and 251 Mb, respectively. In terms of sequencing, our goal for the first stage is to characterize several thousand EST's (from adult worm and cysticerci cDNA libraries) and genomic clones. Results obtained so far from about 16,000 sequenced ESTs from the adult stage, show that only about 40% of the T. solium coding sequences have a previously sequenced homologue. Many of the best hits are found with mammalian genes, especially with humans. However, 1.5% of the hits lack homologues in humans, making these genes immediate candidates for investigation on pharmaco-therapy, diagnostics and vaccination. Most T. solium ESTs are related to gene regulation, and signal transduction. Other important functions are housekeeping, metabolism, cell division, cytoskeleton, proteases, vacuolar transport, hormone response, and extracellular matrix activities. Preliminary results also suggest that the genome of T. solium is not highly repetitive.
我们组建了一个由墨西哥国立自治大学重点实验室组成的联盟，以开展猪带绦虫基因组项目。该项目将为猪带绦虫病/囊尾蚴病的研究提供强大资源，并且与细粒棘球绦虫和多房棘球绦虫表达序列标签（EST）基因组项目一起，将标志着绦虫寄生虫基因组学的到来。我们的项目计划分两个连续阶段进行。第一阶段正在开展，以确定猪带绦虫基因组的一些基本参数。之后，我们将评估第二阶段全面基因组项目的最佳策略。我们通过两种不同方法估计了猪带绦虫基因组大小：对分离的细胞核进行细胞荧光测定法，以及基于约2000个测序基因组克隆、约3000个EST的概率计算，分别得出大小估计值为270 Mb和251 Mb。在测序方面，我们第一阶段的目标是对数千个EST（来自成虫和囊尾蚴cDNA文库）和基因组克隆进行特征描述。到目前为止，从成虫阶段约16000个测序EST中获得的结果表明，猪带绦虫编码序列中只有约40%有先前测序的同源物。许多最佳匹配是与哺乳动物基因，尤其是人类基因。然而，1.5%的匹配在人类中缺乏同源物，使这些基因成为药物治疗、诊断和疫苗接种研究的直接候选对象。大多数猪带绦虫EST与基因调控和信号转导有关。其他重要功能包括管家功能、代谢、细胞分裂、细胞骨架、蛋白酶、液泡运输、激素反应和细胞外基质活性。初步结果还表明，猪带绦虫基因组的重复程度不高。
