Laboratório de Biologia Molecular e Doenças Endêmicas, Instituto Oswaldo Cruz, FIOCRUZ, Rio de Janeiro, Brazil.
Parasit Vectors. 2012 Dec 11;5:290. doi: 10.1186/1756-3305-5-290.
Aedes albopictus is a vector for several fatal arboviruses in tropical and sub-tropical regions of the world. The midgut of the mosquito is the first barrier that pathogens must overcome to establish infection and represents one of the main immunologically active sites of the insect. Nevertheless, little is known about the proteins involved in the defense against pathogens, and even in the processing of food, and the detoxification of metabolites. The identification of proteins exclusively expressed in the midgut is the first step in understanding the complex physiology of this tissue and can provide insight into the mechanisms of pathogen-vector interaction. However, identification of the locally expressed proteins presents a challenge because the Ae. albopictus genome has not been sequenced.
In this study, two-dimensional electrophoresis (2DE) was combined with liquid chromatography in line with tandem mass spectrometry (LC-MS/MS) and data mining to identify the major proteins in the midgut of sugar-fed Ae. albopictus females.
Fifty-six proteins were identified by sequence similarity to entries from the Ae. aegypti genome. In addition, two hypothetical proteins were experimentally confirmed. According to the gene ontology analysis, the identified proteins were classified into 16 clusters of biological processes. Use of the STRING database to investigate protein functional associations revealed five functional networks among the identified proteins, including a network for carbohydrate and amino acid metabolism, a group associated with ATP production and a network of proteins that interact during detoxification of toxic free radicals, among others. This analysis allowed the assignment of a potential role for proteins with unknown function based on their functional association with other characterized proteins.
Our findings represent the first proteome map of the Ae. albopictus midgut and denotes the first steps towards the description of a comprehensive proteome map of this vector. In addition, the data contributes to the functional annotation of Aedes spp. genomes using mass spectrometry-based proteomics data combined with complementary gene prediction methods.
白纹伊蚊是世界热带和亚热带地区几种致命虫媒病毒的传播媒介。蚊子的中肠是病原体必须克服的第一道屏障，是昆虫主要的免疫活性部位之一。然而，人们对参与防御病原体的蛋白质知之甚少，甚至对食物的加工和代谢物的解毒也知之甚少。鉴定仅在中肠表达的蛋白质是了解该组织复杂生理学的第一步，并且可以深入了解病原体-媒介相互作用的机制。然而，由于尚未测序白纹伊蚊基因组，因此鉴定局部表达的蛋白质是一个挑战。
在本研究中，二维电泳（2DE）与在线液相色谱串联质谱（LC-MS/MS）和数据挖掘相结合，以鉴定吸食糖的白纹伊蚊雌性中肠中的主要蛋白质。
通过与埃及伊蚊基因组条目进行序列相似性比对，鉴定出 56 种蛋白质。此外，还实验证实了两种假定蛋白。根据基因本体论分析，鉴定出的蛋白质被分为 16 个生物过程簇。使用 STRING 数据库来研究蛋白质功能关联，揭示了鉴定出的蛋白质之间存在五个功能网络，包括碳水化合物和氨基酸代谢网络、与 ATP 产生相关的一组网络以及在解毒有毒自由基过程中相互作用的蛋白质网络等。这种分析允许根据与其他特征蛋白的功能关联，为具有未知功能的蛋白分配潜在的作用。
我们的研究结果代表了白纹伊蚊中肠的第一个蛋白质组图谱，并标志着朝向描述该媒介全面蛋白质组图谱的第一步。此外，这些数据为使用基于质谱的蛋白质组学数据与互补基因预测方法相结合，对埃及伊蚊属基因组进行功能注释做出了贡献。
