Instituto de Investigaciones en Ingeniería Genética y Biología Molecular "Dr. Hector N. Torres" (INGEBI-CONICET), Vuelta de Obligado 2490, C1428ADN, Buenos Aires, R. Argentina.
J Eukaryot Microbiol. 2013 Jan-Feb;60(1):101-5. doi: 10.1111/jeu.12009. Epub 2012 Dec 3.
Pin1-type peptidyl-prolyl cis/trans isomerases (PPIases) isomerise the peptide bond of specific phosphorylated (Ser/Thr)-Pro residues, regulating various cellular events. Previously, we reported a Pin1-type PPIase in Trypanosoma cruzi, but little is known about its function and subcellular localization. Immunofluorescence analysis revealed that in contrast with Pin1-like proteins from diverse organisms, TcPin1 mainly localized in the cytoplasm and was excluded from the nuclei. In addition, RNAi-mediated downregulation of TbPin1 in Trypanosoma brucei did not abolish cell proliferation. Using yeast two-hybrid assay, we identified a MORN domain-containing protein as putative Pin1-binding partners. These data suggest that Pin1-mediated signaling mechanism plays a different role in protozoan parasites.
Pin1 型肽基脯氨酰顺/反式异构酶(PPIases)可使特定磷酸化(Ser/Thr)-Pro 残基的肽键异构化,从而调节各种细胞事件。以前,我们曾在克氏锥虫中报道过一种 Pin1 型 PPIase,但对其功能和亚细胞定位知之甚少。免疫荧光分析显示,与来自不同生物体的 Pin1 样蛋白不同,TcPin1 主要定位于细胞质中,而不位于核内。此外,RNAi 介导的在布氏锥虫中 TbPin1 的下调并未阻止细胞增殖。通过酵母双杂交实验,我们鉴定了一个含有 MORN 结构域的蛋白作为潜在的 Pin1 结合伴侣。这些数据表明,Pin1 介导的信号机制在原生动物寄生虫中发挥着不同的作用。