Muzulin Patricia Marcela, Kamenetzky Laura, Gutierrez Ariana Marcela, Guarnera Eduardo Alfredo, Rosenzvit Mara Cecilia
Departamento de Parasitología, Instituto Nacional de Enfermedades Infecciosas ANLIS Dr. Carlos G. Malbrán, Av. Vélez Sarsfield 563, Buenos Aires (1281), Argentina.
Exp Parasitol. 2008 Feb;118(2):156-64. doi: 10.1016/j.exppara.2007.07.004. Epub 2007 Aug 3.
Echinococcus granulosus AgB gene family is constituted by five gene loci. In a previous study, we analyzed the strain variation of EgAgB2/B4 sequences. Here, we have analyzed, by SSCP and sequencing, 250 genomic clones of EgAgB1/B3/B5 gene cluster from five E. granulosus strains. Several new EgAgB genomic variants were found. EgAgB1 and EgAgB3 genomic sequences grouped E. granulosus strains by phylogenetic tools in two clusters: one formed by G1/G2 and the other by G5, G6/G7 strains, in accordance with other molecular markers. EgAgB5 genomic and cDNA sequences were only found in G1/G2 cluster. Reverse transcription-PCR analysis using subunit specific primers revealed that all the EgAgB genes were transcribed in G1 and G7 strains with the exception of EgAgB5 transcripts that were not detected in G7 strain. Interestingly, AgB2 transcripts that were probably processed by an aberrant splicing mechanism leading to a non-functional B2 protein were found in G7 strain.
细粒棘球绦虫AgB基因家族由五个基因位点组成。在先前的一项研究中，我们分析了EgAgB2/B4序列的菌株变异情况。在此，我们通过单链构象多态性（SSCP）和测序分析了来自五个细粒棘球绦虫菌株的250个EgAgB1/B3/B5基因簇的基因组克隆。发现了几个新的EgAgB基因组变体。通过系统发育工具，EgAgB1和EgAgB3基因组序列将细粒棘球绦虫菌株分为两个簇：一个由G1/G2组成，另一个由G5、G6/G7菌株组成，这与其他分子标记一致。EgAgB5基因组和cDNA序列仅在G1/G2簇中发现。使用亚基特异性引物的逆转录聚合酶链反应（RT-PCR）分析表明，除了在G7菌株中未检测到的EgAgB5转录本外，所有EgAgB基因在G1和G7菌株中均有转录。有趣的是，在G7菌株中发现了可能通过异常剪接机制加工导致无功能B2蛋白的AgB2转录本。
