Yau Raymond, Pavloudi Christina, Zeng Yingying, Saw Jimmy, Eleftherianos Ioannis
Department of Biological Sciences, The George Washington University, Washington, DC, United States of America.
European Marine Biological Resource Centre-European Research Infrastructure Consortium (EMBRC-ERIC), Paris, France.
PLoS One. 2025 May 16;20(5):e0323657. doi: 10.1371/journal.pone.0323657. eCollection 2025.
The fruit fly Drosophila melanogaster is a vital model for studying the microbiome due to the availability of genetic resources and procedures. To understand better the importance of microbial composition in shaping immune modulation, we can investigate the role of the microbiota through parasitic infection. For this, we use entomopathogenic nematodes (EPN) of the genus Steinernema which exhibit remarkable ability to efficiently infect a diverse array of insect species, facilitated by the mutualistic bacteria Xenorhabdus found within their gut. To examine the microbiome changes in D. melanogaster larvae in response to Steinernema nematode infection, D. melanogaster late second to early third instar larvae were exposed separately to S. carpocapsae and S. hermaphroditum infective juveniles. We have found that S. carpocapsae infective juveniles are more pathogenic to D. melanogaster larvae compared to the closely related S. hermaphroditum. Our microbiome analysis also indicates substantial changes in the size and composition of the D. melanogaster larval microbiome during infection with either nematode species compared to the uninfected controls. Our results serve as a foundation for future studies to elucidate the entomopathogenic-specific effector molecules that alter the D. melanogaster microbiome and understand the role of the microbiome in regulating insect anti-nematode immune processes.
由于遗传资源和实验方法的可得性，果蝇（Drosophila melanogaster）是研究微生物组的重要模型。为了更好地理解微生物组成在塑造免疫调节中的重要性，我们可以通过寄生虫感染来研究微生物群的作用。为此，我们使用斯氏线虫属（Steinernema）的昆虫病原线虫（EPN），它们在其肠道内共生的嗜线虫致病杆菌（Xenorhabdus）的帮助下，表现出高效感染多种昆虫物种的显著能力。为了检测黑腹果蝇幼虫在感染斯氏线虫后微生物组的变化，将黑腹果蝇二龄晚期至三龄早期幼虫分别暴露于苹果蠹蛾斯氏线虫（S. carpocapsae）和雌雄同体斯氏线虫（S. hermaphroditum）的感染性幼虫中。我们发现，与亲缘关系较近的雌雄同体斯氏线虫相比，苹果蠹蛾斯氏线虫的感染性幼虫对黑腹果蝇幼虫的致病性更强。我们的微生物组分析还表明，与未感染的对照组相比，在感染任何一种线虫物种期间，黑腹果蝇幼虫微生物组的大小和组成都发生了显著变化。我们的研究结果为未来的研究奠定了基础，以阐明改变黑腹果蝇微生物组的昆虫病原特异性效应分子，并了解微生物组在调节昆虫抗线虫免疫过程中的作用。
