BACKGROUND The marine annelid Platynereis dumerilii (Polychaeta, Nereididae) has been recognized as a slow-evolving lophotrochozoan that attracts increasing attention as a valuable model for evolutionary and developmental research. Here, we analyzed its immune-related transcriptome. For targeted identification of immune-induced genes we injected bacterial lipopolysaccharide, a commonly used elicitor of innate immune responses, and applied the suppression subtractive hybridization technique that selectively amplifies cDNAs of differentially expressed genes. RESULTS Sequence analysis of 288 cDNAs revealed induced expression of numerous genes whose potential homologues from other animals mediate recognition of infection (e.g. complement receptor CD35), signaling (e.g. myc and SOCS), or act as effector molecules like ferritins and the bactericidal permeability-increasing protein. Interestingly, phylogenetic analyses implicate that immune-related genes identified in P. dumerilii are more related to counterparts from Deuterostomia than are those from Ecdysozoa, similarly as recently described for opsin and intron-rich genes. CONCLUSION Obtained results may allow for a better understanding of Platynereis immunity and support the view that P. dumerilii represents a suitable model for analyzing immune responses of Lophotrochozoa.

中文翻译：

---

恶性疟原虫模型，海洋轮虫杜氏侧柏的免疫相关转录组的分析。

背景技术海洋无脊椎动物Ptyernereis dumerilii（Polychaeta，Nereididae）被认为是一种缓慢发展的风光虫，作为一种进化和发育研究的有价值的模型吸引了越来越多的关注。在这里，我们分析了其免疫相关的转录组。为了有针对性地识别免疫诱导的基因，我们注入了细菌脂多糖（一种先天性免疫应答的常用引发剂），并应用了抑制消减杂交技术，该技术选择性地扩增差异表达基因的cDNA。结果对288个cDNA的序列分析表明，许多基因的诱导表达，这些基因的其他动物的潜在同源物介导感染的识别（例如补体受体CD35），信号传导（例如myc和SOCS），或充当诸如铁蛋白和杀菌通透性增加蛋白之类的效应分子。有趣的是，系统发育分析表明，与最近的视蛋白和富含内含子的基因类似，在杜氏假单胞菌中鉴定的与免疫相关的基因与从蜕皮癖的对应物相比，与蜕皮假单胞菌的同源性更高。结论获得的结果可能使人们更好地了解侧柏的免疫力，并支持以下观点：杜氏假单胞菌代表了一种合适的模型，用于分析恶性疟原虫的免疫反应。