Olfaction contributes to many crucial behaviors in insects, such as foraging, locating hosts, mating, and avoiding predators. In the first step of the olfaction process in insects, odorant-binding proteins (OBPs) bind with the odorants and transport hydrophobic odorants. OBPs are also believed to accelerate the termination of the odorant response. The oriental fruit fly, Bactrocera dorsalis, is one of the most destructive fruit-eating pests, causing enormous economic losses to the fruit and vegetable industry worldwide. However, information relating to the number, diversity, and expression patterns of OBPs still remains fragmented in this insect pest. Here, we attempted to identify the OBPs in B. dorsalis using genomic and transcriptomic information. In this study, we expanded the repository of B. dorsalis OBPs to 49. Phylogenetic analysis of BdorOBPs with other species revealed that these proteins grouped into four subfamilies. Furthermore, we determined the expression profiles in six body parts (namely, the legs, wings, antenna, cuticles of the head, thorax, and abdomen) and five internal tissues (namely, the fat body, midgut, Malpighian tubule, testis, and ovary). The results indicated that 21 BdorOBPs showed high expression levels in the antenna, legs, and head cuticles and may thus perform olfactory functions, which corroborates previous evidence. Two BdorOBPs were specifically expressed in the abdomen cuticles. Nineteen OBPs were highly expressed in the fat body, while four OBPs were highly expressed in the reproductive organs. This indicated that they may have physiological roles other than in chemoreception. In summary, our results contribute to the knowledge base of insect OBPs and provide a foundation for the further study of the molecular mechanisms of chemoreception in B. dorsalis.

嗅觉有助于昆虫中许多重要的行为，例如觅食，定位宿主，交配和避开捕食者。在昆虫嗅觉过程的第一步中，加味剂结合蛋白（OBP）与加味剂结合并转运疏水性加味剂。还认为OBP可以加速气味反应的终止。东方果蝇小实蝇（Bactrocera dorsalis）是最具破坏性的食水果害虫之一，给全世界的水果和蔬菜行业造成了巨大的经济损失。但是，与OBP的数量，多样性和表达方式有关的信息在该害虫中仍然是零碎的。在这里，我们尝试鉴定背果双歧杆菌中的OBP使用基因组和转录组信息。在这项研究中，我们扩展了背侧双歧杆菌的储存库OBPs到49. BdorOBPs与其他物种的系统发育分析表明，这些蛋白质分为四个亚科。此外，我们确定了六个身体部位（即腿，翅膀，触角，头部，胸部和腹部的表皮）和五个内部组织（即脂肪体，中肠，马尔皮基小管，睾丸和子房）。结果表明21种BdorOBP在触角，腿和头皮中表现出高表达水平，因此可能具有嗅觉功能，这证实了以前的证据。在腹部角质层中特异性表达了两个BdorOBP。在脂肪体内高表达19种OBP，而在生殖器官中高表达4种OBP。这表明它们可能除了化学感受外还具有生理作用。综上所述，B.背侧。