Plant Biotechnology Research Group, WA State Agricultural Biotechnology Centre, School of Biological Sciences and Biotechnology, Murdoch University, Perth, Australia.
Int J Parasitol. 2012;42(3):225-37. doi: 10.1016/j.ijpara.2011.11.010. Epub 2012 Jan 21.
The migratory endoparasitic root lesion nematode Pratylenchus thornei is a major pest of the cereals wheat and barley. In what we believe to be the first global transcriptome analysis for P. thornei, using Roche GS FLX sequencing, 787,275 reads were assembled into 34,312 contigs using two assembly programs, to yield 6,989 contigs common to both. These contigs were annotated, resulting in functional assignments for 3,048. Specific transcripts studied in more detail included carbohydrate active enzymes potentially involved in cell wall degradation, neuropeptides, putative plant nematode parasitism genes, and transcripts that could be secreted by the nematode. Transcripts for cell wall degrading enzymes were similar to bacterial genes, suggesting that they were acquired by horizontal gene transfer. Contigs matching 14 parasitism genes found in sedentary endoparasitic nematodes were identified. These genes are thought to function in suppression of host defenses and in feeding site development, but their function in P. thornei may differ. Comparison of the common contigs from P. thornei with other nematodes showed that 2,039 were common to sequences of the Heteroderidae, 1,947 to the Meloidogynidae, 1,218 to Radopholus similis, 1,209 matched expressed sequence tags (ESTs) of Pratylenchus penetrans and Pratylenchus vulnus, and 2,940 to contigs of Pratylenchus coffeae. There were 2,014 contigs common to Caenarhabditis elegans, with 15.9% being common to all three groups. Twelve percent of contigs with matches to the Heteroderidae and the Meloidogynidae had no homology to any C. elegans protein. Fifty-seven percent of the contigs did not match known sequences and some could be unique to P. thornei. These data provide substantial new information on the transcriptome of P. thornei, those genes common to migratory and sedentary endoparasitic nematodes, and provide additional understanding of genes required for different forms of parasitism. The data can also be used to identify potential genes to study host interactions and for crop protection.
迁移性内寄生根结线虫 Pratylenchus thornei 是小麦和大麦等谷物的主要害虫。在我们认为是首次针对 P. thornei 的全球转录组分析中，我们使用 Roche GS FLX 测序技术，将 787,275 条reads 组装成 34,312 个 contigs，使用两种组装程序，生成 6,989 个共同的 contigs。这些 contigs 进行了注释，为 3,048 个产生了功能分配。更详细研究的特定转录本包括可能参与细胞壁降解的碳水化合物活性酶、神经肽、假定的植物线虫寄生基因以及可以由线虫分泌的转录本。细胞壁降解酶的转录本与细菌基因相似，表明它们是通过水平基因转移获得的。鉴定出与定居内寄生线虫中发现的 14 种寄生基因匹配的 contigs。这些基因被认为在抑制宿主防御和在取食部位发育中起作用，但它们在 P. thornei 中的功能可能不同。将 P. thornei 的常见 contigs 与其他线虫进行比较表明，2,039 个与 Heteroderidae 的序列共有，1,947 个与 Meloidogynidae 共有，1,218 个与 Radopholus similis 共有，1,209 个与 Pratylenchus penetrans 和 Pratylenchus vulnus 的表达序列标签 (EST) 共有，2,940 个与 Pratylenchus coffeae 的 contigs 共有。有 2,014 个 contigs 与 Caenorhabditis elegans 共有，其中 15.9%与所有三个组共有。与 Heteroderidae 和 Meloidogynidae 匹配的 contigs 中有 12%与任何 C. elegans 蛋白都没有同源性。57%的 contigs与已知序列不匹配，有些可能是 P. thornei 所特有的。这些数据为 P. thornei 的转录组提供了大量新信息，为迁移性和定居性内寄生线虫共有基因提供了更多的了解，并为不同形式的寄生所需的基因提供了更多的了解。这些数据还可用于鉴定潜在的基因来研究宿主相互作用和作物保护。
