Faria-Campos Alessandra C, Moratelli Fernanda S, Mendes Isabella K, Ortolani Paula L, Oliveira Guilherme C, Campos Sérgio V A, Ortega J Miguel, Franco Glória R
Departamento de Bioquímica e Imunologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Av. Antônio Carlos 6627, 31270-901 Belo Horzonte, MG, Brazil.
Mem Inst Oswaldo Cruz. 2006 Sep;101 Suppl 1:161-5. doi: 10.1590/s0074-02762006000900026.
The number of sequences generated by genome projects has increased exponentially, but gene characterization has not followed at the same rate. Sequencing and analysis of full-length cDNAs is an important step in gene characterization that has been used nowadays by several research groups. In this work, we have selected Schistosoma mansoni clones for full-length sequencing, using an algorithm that investigates the presence of the initial methionine in the parasite sequence based on the positions of alignment start between two sequences. BLAST searches to produce such alignments have been performed using parasite expressed sequence tags produced by Minas Gerais Genome Network against sequences from the database Eukaryotic Cluster of Orthologous Groups (KOG). This procedure has allowed the selection of clones representing 398 proteins which have not been deposited as S. mansoni complete CDS in any public database. Dedicated sequencing of 96 of such clones with reads from both 5' and 3' ends has been performed. These reads have been assembled using PHRAP, resulting in the production of 33 full-length sequences that represent novel S. mansoni proteins. These results shall contribute to construct a more complete view of the biology of this important parasite.
基因组计划所产生的序列数量呈指数级增长，但基因特征描述却未能以同样的速度跟进。全长cDNA的测序和分析是基因特征描述中的重要一步，目前已有多个研究团队采用。在这项工作中，我们选择了曼氏血吸虫克隆进行全长测序，使用一种算法，该算法根据两条序列之间比对起始位置来研究寄生虫序列中起始甲硫氨酸的存在情况。利用米纳斯吉拉斯基因组网络产生的寄生虫表达序列标签，针对来自直系同源群真核生物数据库（KOG）的序列进行BLAST搜索以产生此类比对。这一程序使得我们能够选择代表398种蛋白质的克隆，这些蛋白质在任何公共数据库中都未作为曼氏血吸虫完整编码序列（CDS）存入。已对其中96个克隆进行了5'端和3'端的专门测序。这些测序读数已使用PHRAP进行组装，从而产生了代表曼氏血吸虫新蛋白质的33条全长序列。这些结果将有助于构建对这种重要寄生虫生物学更完整的认识。
