Ritagliati Carla, Alonso Victoria L, Manarin Romina, Cribb Pamela, Serra Esteban C
Instituto de Biología Molecular y Celular de Rosario (IBR), Consejo Nacional de Investigaciones Científicas y Técnicas, Rosario, Argentina.
Instituto de Biología Molecular y Celular de Rosario (IBR), Consejo Nacional de Investigaciones Científicas y Técnicas, Rosario, Argentina; Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario (UNR), Rosario, Argentina.
PLoS Negl Trop Dis. 2015 Apr 15;9(4):e0003725. doi: 10.1371/journal.pntd.0003725. eCollection 2015 Apr.
Trypanosoma cruzi is a protozoan pathogen responsible for Chagas disease. Current therapies are inadequate because of their severe host toxicity and numerous side effects. The identification of new biotargets is essential for the development of more efficient therapeutic alternatives. Inhibition of sirtuins from Trypanosoma brucei and Leishmania ssp. showed promising results, indicating that these enzymes may be considered as targets for drug discovery in parasite infection. Here, we report the first characterization of the two sirtuins present in T. cruzi.
Dm28c epimastigotes that inducibly overexpress TcSIR2RP1 and TcSIR2RP3 were constructed and used to determine their localizations and functions. These transfected lines were tested regarding their acetylation levels, proliferation and metacyclogenesis rate, viability when treated with sirtuin inhibitors and in vitro infectivity.
TcSIR2RP1 and TcSIR2RP3 are cytosolic and mitochondrial proteins respectively. Our data suggest that sirtuin activity is important for the proliferation of T. cruzi replicative forms, for the host cell-parasite interplay, and for differentiation among life-cycle stages; but each one performs different roles in most of these processes. Our results increase the knowledge on the localization and function of these enzymes, and the overexpressing T. cruzi strains we obtained can be useful tools for experimental screening of trypanosomatid sirtuin inhibitors.
克氏锥虫是引发恰加斯病的原生动物病原体。由于目前的疗法具有严重的宿主毒性和众多副作用，因而并不理想。鉴定新的生物靶点对于开发更有效的治疗方案至关重要。抑制布氏锥虫和利什曼原虫属的沉默调节蛋白显示出有前景的结果，这表明这些酶可被视为寄生虫感染药物研发的靶点。在此，我们报道了克氏锥虫中存在的两种沉默调节蛋白的首次特征描述。
构建了可诱导过表达TcSIR2RP1和TcSIR2RP3的Dm28c型前鞭毛体，并用于确定它们的定位和功能。对这些转染细胞系进行了乙酰化水平、增殖和循环体生成率、用沉默调节蛋白抑制剂处理后的活力以及体外感染性的测试。
TcSIR2RP1和TcSIR2RP3分别是胞质蛋白和线粒体蛋白。我们的数据表明，沉默调节蛋白活性对于克氏锥虫复制型的增殖、宿主细胞与寄生虫的相互作用以及生命周期各阶段之间的分化很重要；但在大多数这些过程中，它们各自发挥着不同的作用。我们的结果增加了对这些酶的定位和功能的了解，并且我们获得的过表达克氏锥虫菌株可作为锥虫沉默调节蛋白抑制剂实验筛选的有用工具。
