Microbiome turnover during offspring development varies with maternal care, but not moult, in a hemimetabolous insect

The ecological success of insects often depends on their association with beneficial microbes. However, insect development involves repeated moults, which can have dramatic effects on their microbial communities. Here, we investigated whether and how moulting affects the microbiome of a hemimetabolous insect, and whether maternal care can modulate these effects. We reared European earwig juveniles with or without mothers and used 16S rRNA metabarcoding to analyse the whole microbiome of eggs, recently and old moulted individuals at four developmental stages and the resulting adults. The 218 samples obtained showed that the microbiome diversity changed non-linearly during development and that these changes were associated with bacterial biomarkers. Surprisingly, these changes did not occur during moulting, but rather between the beginning and end of certain developmental stages. We also found that access to maternal care affected the microbiome of both juveniles and adults, even when the last contact with mothers was two months before adulthood. Overall, these results provide new insights into our understanding of the (in)stability of the microbiome in hemimetabolous insects and its independence from moult. More generally, they question the role of microbiome acquisition through maternal care in maintaining family life in species where this behaviour is facultative. This repositery contains all dataset that allow to reproduce this study (16S rRNA sequences in .fastq format, the R script and the informative file realted with the sequences (env_succession.xlsm).昆虫的生态成功往往与其与有益微生物的共生关系密不可分。然而，昆虫发育过程中会反复经历蜕皮事件，这会对其微生物群落产生显著影响。本研究旨在探究蜕皮是否以及如何影响半变态昆虫（hemimetabolous insect）的微生物组，同时验证母性抚育能否调控此类影响。我们设置了有母虫抚育与无母虫抚育的欧洲蠼螋（European earwig）幼虫饲养组，并采用16S rRNA 宏条形码测序（16S rRNA metabarcoding）技术，对卵、刚蜕皮及蜕皮一段时间后的个体在四个发育阶段的完整微生物组，以及最终发育为成虫的样本进行了分析。本次研究共获取218份样本，结果显示微生物组多样性在发育过程中呈非线性变化，且该变化与特定细菌生物标志物密切相关。出乎意料的是，此类变化并未发生在蜕皮当下，而是出现在特定发育阶段的起始与结束之间。我们还发现，即便子代与母虫的最后一次接触距离成虫期已有两个月，母性抚育仍会对子代幼虫和成虫的微生物组产生显著影响。综上，本研究为理解半变态昆虫微生物组的（不）稳定性及其与蜕皮过程的独立性提供了全新视角。更广泛而言，本研究也对兼性母育物种中，通过母性抚育获取微生物组对维持家族社群的作用提出了质疑。 本仓库包含可复现本研究的全部数据集，具体包括格式为.fastq的16S rRNA测序序列、R脚本及与测序序列相关的说明文件env_succession.xlsm。