Alvite Gabriela, Garrido Natalia, Kun Alejandra, Paulino Margot, Esteves Adriana
Sección Bioquímica, Facultad de Ciencias, Universidad de la República, Montevideo, Uruguay.
Sección Bioquímica, Facultad de Ciencias, Universidad de la República, Montevideo, Uruguay; Instituto de Investigaciones Biológicas Clemente Estable, Montevideo, Uruguay.
PLoS One. 2014 Oct 27;9(10):e111204. doi: 10.1371/journal.pone.0111204. eCollection 2014.
Two fatty acid binding proteins, MvFABPa and MvFABPb were identified in the parasite Mesocestoides vogae (Platyhelmithes, Cestoda). Fatty acid binding proteins are small intracellular proteins whose members exhibit great diversity. Proteins of this family have been identified in many organisms, of which Platyhelminthes are among the most primitive. These proteins have particular relevance in flatworms since de novo synthesis of fatty acids is absent. Fatty acids should be captured from the media needing an efficient transport system to uptake and distribute these molecules. While HLBPs could be involved in the shuttle of fatty acids to the surrounding host tissues and convey them into the parasite, FABPs could be responsible for the intracellular trafficking. In an effort to understand the role of MvFABPs in fatty acid transport of M. vogae larvae, we analysed the intracellular localization of both MvFABPs and the co-localization with in vivo uptake of fatty acid analogue BODIPY FL C16. Immunohistochemical studies on larvae sections using specific antibodies, showed a diffuse cytoplasmic distribution of each protein with some expression in nuclei and mitochondria. MvFABPs distribution was confirmed by mass spectrometry identification from 2D-electrophoresis of larvae subcellular fractions. This work is the first report showing intracellular distribution of MvFABPs as well as the co-localization of these proteins with the BODIPY FL C16 incorporated from the media. Our results suggest that fatty acid binding proteins could target fatty acids to cellular compartments including nuclei. In this sense, M. vogae FABPs could participate in several cellular processes fulfilling most of the functions attributed to vertebrate's counterparts.
在寄生虫沃氏中殖孔绦虫（扁形动物门，绦虫纲）中鉴定出了两种脂肪酸结合蛋白，即MvFABPa和MvFABPb。脂肪酸结合蛋白是一类小的细胞内蛋白，其成员具有很大的多样性。该家族的蛋白已在许多生物体中被鉴定出来，其中扁形动物是最原始的生物之一。这些蛋白在扁形虫中具有特殊的相关性，因为它们无法进行脂肪酸的从头合成。脂肪酸需要从周围环境中摄取，这就需要一个高效的转运系统来摄取和分布这些分子。虽然HLBPs可能参与脂肪酸向周围宿主组织的穿梭并将其输送到寄生虫中，但FABPs可能负责细胞内的运输。为了了解MvFABPs在沃氏中殖孔绦虫幼虫脂肪酸运输中的作用，我们分析了这两种MvFABPs的细胞内定位以及它们与脂肪酸类似物BODIPY FL C16体内摄取的共定位情况。使用特异性抗体对幼虫切片进行免疫组织化学研究，结果显示每种蛋白在细胞质中呈弥漫性分布，在细胞核和线粒体中也有一些表达。通过对幼虫亚细胞组分的二维电泳进行质谱鉴定，证实了MvFABPs的分布。这项工作是首次报道MvFABPs的细胞内分布以及这些蛋白与从培养基中摄取的BODIPY FL C16的共定位情况。我们的结果表明，脂肪酸结合蛋白可能将脂肪酸靶向到包括细胞核在内的细胞区室。从这个意义上说，沃氏中殖孔绦虫FABPs可能参与多种细胞过程，履行大多数归因于脊椎动物对应蛋白的功能。
