Institute of Integrative Biology (IBZ), ETH Zürich, Universitätsstrasse 16, 8092 Zürich, Switzerland.
BMC Genomics. 2010 Feb 15;11:110. doi: 10.1186/1471-2164-11-110.
The bumblebee, Bombus terrestris (Order Hymenoptera), is of widespread importance. This species is extensively used for commercial pollination in Europe, and along with other Bombus spp. is a key member of natural pollinator assemblages. Furthermore, the species is studied in a wide variety of biological fields. The objective of this project was to create a B. terrestris EST resource that will prove to be valuable in obtaining a deeper understanding of this significant social insect.
A normalised cDNA library was constructed from the thorax and abdomen of B. terrestris workers in order to enhance the discovery of rare genes. A total of 29'428 ESTs were sequenced. Subsequent clustering resulted in 13'333 unique sequences. Of these, 58.8 percent had significant similarities to known proteins, with 54.5 percent having a "best-hit" to existing Hymenoptera sequences. Comparisons with the honeybee and other insects allowed the identification of potential candidates for gene loss, pseudogene evolution, and possible incomplete annotation in the honeybee genome. Further, given the focus of much basic research and the perceived threat of disease to natural and commercial populations, the immune system of bumblebees is a particularly relevant component. Although the library is derived from unchallenged bees, we still uncover transcription of a number of immune genes spanning the principally described insect immune pathways. Additionally, the EST library provides a resource for the discovery of genetic markers that can be used in population level studies. Indeed, initial screens identified 589 simple sequence repeats and 854 potential single nucleotide polymorphisms.
The resource that these B. terrestris ESTs represent is valuable for ongoing work. The ESTs provide direct evidence of transcriptionally active regions, but they will also facilitate further functional genomics, gene discovery and future genome annotation. These are important aspects in obtaining a greater understanding of this key pollinator species.
熊蜂（膜翅目）具有广泛的重要性。该物种在欧洲被广泛用于商业授粉，与其他熊蜂属物种一起，是自然授粉者组合的关键成员。此外，该物种在广泛的生物领域进行研究。本项目的目的是创建一个 B. terrestris EST 资源，这将有助于更深入地了解这种重要的社会性昆虫。
为了增强稀有基因的发现，我们从 B. terrestris 工蜂的胸部和腹部构建了一个正常化的 cDNA 文库。总共测序了 29428 个 EST。随后的聚类导致了 13333 个独特的序列。其中，58.8%与已知蛋白具有显著相似性，54.5%与现有的膜翅目序列具有“最佳命中”。与蜜蜂和其他昆虫的比较允许识别基因丢失、假基因进化和蜜蜂基因组中可能不完全注释的潜在候选者。此外，鉴于基础研究的重点和对自然和商业种群疾病的威胁，熊蜂的免疫系统是一个特别相关的组成部分。尽管该文库源自未经挑战的蜜蜂，但我们仍然发现了跨越主要描述的昆虫免疫途径的许多免疫基因的转录。此外，EST 文库为发现可用于群体水平研究的遗传标记提供了资源。事实上，初步筛选确定了 589 个简单重复序列和 854 个潜在的单核苷酸多态性。
这些 B. terrestris EST 所代表的资源对于正在进行的工作具有价值。EST 提供了转录活性区域的直接证据，但它们也将促进进一步的功能基因组学、基因发现和未来的基因组注释。这是更深入了解这种关键授粉物种的重要方面。
