EPA Victoria, Water Sciences, Melbourne, Australia; School of Biological Sciences, Monash University, Australia; Department of Biosciences, Åbo Akademi University, Finland.
Life Sciences, Glasgow Caledonian University, UK.
Environ Pollut. 2021 Feb 1;270:116286. doi: 10.1016/j.envpol.2020.116286. Epub 2020 Dec 13.
Although many pharmaceutical compounds (and their metabolites) can induce harmful impacts at the molecular, physiological and behavioural levels, their underlying mechanistic associations have remained largely unexplored. Here, we utilized RNA-Seq to build a whole brain transcriptome profile to examine the impact of a common endocrine disrupting pharmaceutical (17α-ethinyl estradiol, EE2) on reproductive behaviour in wild guppies (Poecilia reticulata). Specifically, we annotated 16,791 coding transcripts in whole brain tissue in relation to the courtship behaviour (i.e. sigmoid display) of EE2 exposed (at environmentally relevant concentration of 8 ng/L for 28-days) and unexposed guppies. Further, we obtained 10,960 assembled transcripts matching in the non-coding orthologous genomes. Behavioural responses were assessed using a standard mate choice experiment, which allowed us to disentangle chemical cues from visual cues. We found that a high proportion of the RNAseq reads aligned back to our de novo assembled transcriptome with 80.59% mapping rate. Behavioural experiments showed that when males were presented only with female visual cues, there was a significant interaction between male treatment and female treatment in the time spent in the preference zone. This is one of the first studies to show that transcriptome-wide changes are associated with the reproductive behaviour of fish: EE2 exposed male guppies that performed high levels of courtship had a gene profile that deviated the most from the other treatment groups, while both non-courting EE2 and control males had similar gene signatures. Using Gene Ontology pathway analysis, our study shows that EE2-exposed males had gene transcripts enriched for pathways associated with altered immunity, starvation, altered metabolism and spermatogenesis. Our study demonstrates that multiple gene networks orchestrate courting behaviour, emphasizing the importance of investigating impacts of pharmaceuticals on gene networks instead of single genes.
虽然许多药物化合物（及其代谢物）会在分子、生理和行为水平上产生有害影响，但它们的潜在机制关联在很大程度上仍未得到探索。在这里，我们利用 RNA-Seq 构建了全脑转录组图谱，以研究一种常见的内分泌干扰药物（17α-乙炔雌二醇，EE2）对野生孔雀鱼（Poecilia reticulata）生殖行为的影响。具体来说，我们在大脑组织中注释了 16791 个与 EE2 暴露（在环境相关浓度 8ng/L 下暴露 28 天）和未暴露的孔雀鱼求爱行为（即正弦形展示）相关的编码转录本。此外，我们获得了 10960 个与非编码同源基因组匹配的组装转录本。行为反应通过标准的择偶实验进行评估，这使我们能够从视觉线索中分离化学线索。我们发现，高比例的 RNAseq 读数与我们从头组装的转录组对齐，映射率为 80.59%。行为实验表明，当雄性只呈现雌性的视觉线索时，雄性处理和雌性处理之间在偏好区停留的时间存在显著的相互作用。这是首次表明转录组变化与鱼类生殖行为相关的研究之一：表现出高水平求爱的 EE2 暴露雄性孔雀鱼的基因谱与其他处理组的差异最大，而不进行求爱的 EE2 和对照雄性的基因特征相似。使用基因本体论（GO）途径分析，我们的研究表明，EE2 暴露的雄性有丰富的与免疫改变、饥饿、代谢改变和精子发生相关的途径的基因转录本。我们的研究表明，多个基因网络协调求爱行为，强调研究药物对基因网络而不是单个基因的影响的重要性。
