State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Yangling 712100, China.
State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&F University, Yangling 712100, China.
Pestic Biochem Physiol. 2023 Feb;190:105335. doi: 10.1016/j.pestbp.2022.105335. Epub 2023 Jan 2.
Antimicrobial peptides (AMPs) play essential roles in defending against various invading pathogens. Although antibacterial or antifungal properties of AMPs have been well characterized, the contribution of AMPs to immune defenses against viruses especially baculoviruses is still unclear. In this study, four full-length AMP genes (Ldcec, Ldatt, Ldglo and Ldmor) that encode the cecropin, attacin, gloverin and moricin, respectively, were characterized in Lymantria dispar (Asian gypsy moth). All four AMPs were cationic peptides and exhibited hydrophilicity. Structural analysis showed that the Ldcec and Ldmor were α-helical peptides. Tissue-specific Ldcec expression was the highest in fat body, while expression of Ldatt, Ldglo and Ldmor was the highest in epidermis. All four AMP genes were expressed during all developmental stages with the highest expression in the pupa and adult. Compared to mock infection, expression of these four AMP genes were significantly induced following Lymantria dispar multiple nucleopolyhedrovirus (LdMNPV) challenge and sharply increased at 72 h post infection. After Ldglo gene silencing, the DNA replication levels of LdMNPV in L. dispar larvae significantly increased at 48 and 72 h post infection, indicating that the Ldglo could suppress the DNA replication of LdMNPV. Our results suggest that four AMPs of L. dispar may play important roles in antiviral immunity against LdMNPV.
抗菌肽（AMPs）在抵御各种入侵病原体方面发挥着重要作用。尽管 AMPs 的抗菌或抗真菌特性已经得到很好的表征，但 AMPs 对病毒（尤其是杆状病毒）免疫防御的贡献仍不清楚。在这项研究中，我们在舞毒蛾（亚洲舞毒蛾）中鉴定了四个全长 AMP 基因（Ldcec、Ldatt、Ldglo 和 Ldmor），分别编码 Cecropin、Attacin、Gloverin 和 Moricin。这四种 AMP 都是阳离子肽，具有亲水性。结构分析表明，Ldcec 和 Ldmor 是α-螺旋肽。组织特异性 Ldcec 在脂肪体中的表达最高，而 Ldatt、Ldglo 和 Ldmor 的表达在表皮中最高。这四个 AMP 基因在所有发育阶段都有表达，在蛹和成虫中表达最高。与mock 感染相比，这四个 AMP 基因在舞毒蛾多核多角体病毒（LdMNPV）感染后显著诱导表达，并在感染后 72 小时急剧增加。在 Ldglo 基因沉默后，LdMNPV 在舞毒蛾幼虫中的 DNA 复制水平在感染后 48 和 72 小时显著增加，表明 Ldglo 可以抑制 LdMNPV 的 DNA 复制。我们的结果表明，舞毒蛾的四种 AMP 可能在抗病毒免疫中发挥重要作用。
