Liu Xiaomi, Culbert Erica L, Brisson Jennifer A
Department of Biology, University of Rochester, Rochester, NY 14627, USA.
Insects. 2021 Jun 8;12(6):533. doi: 10.3390/insects12060533.
Epigenetic mechanisms modulate gene expression levels during development, shaping how a single genome produces a diversity of phenotypes. Here, we begin to explore the epigenetic regulation of sexual dimorphism in pea aphids () by focusing on microRNAs. Previous analyses of microRNAs in aphids have focused solely on females, so we performed deep sequencing of a sample containing early-stage males. We used this sample, plus samples from Genbank, to find 207 novel pea aphid microRNA coding loci. We localized microRNA loci to a chromosome-level assembly of the pea aphid genome and found that those on the X chromosome have lower overall expression compared to those on autosomes. We then identified a set of 19 putative male-biased microRNAs and found them enriched on the X chromosome. Finally, we performed protein-coding RNA-Seq of first instar female and male pea aphids to identify genes with lower expression in males. 10 of these genes were predicted targets of the 19 male-biased microRNAs. Our study provides the most complete set of microRNAs in the pea aphid to date and serves as foundational work for future studies on the epigenetic control of sexual dimorphism.
表观遗传机制在发育过程中调节基因表达水平，决定了单个基因组如何产生多种表型。在此，我们通过聚焦于微小RNA开始探索豌豆蚜（）中性二态性的表观遗传调控。此前对蚜虫微小RNA的分析仅聚焦于雌性，因此我们对一个包含早期雄性的样本进行了深度测序。我们利用这个样本以及来自基因库的样本，找到了207个新的豌豆蚜微小RNA编码位点。我们将微小RNA位点定位到豌豆蚜基因组的染色体水平组装上，发现X染色体上的那些位点与常染色体上的相比总体表达较低。然后我们鉴定出一组19个推定的雄性偏向性微小RNA，并发现它们在X染色体上富集。最后，我们对一龄雌性和雄性豌豆蚜进行了蛋白质编码RNA测序，以鉴定在雄性中表达较低的基因。其中10个基因是这19个雄性偏向性微小RNA的预测靶标。我们的研究提供了迄今为止豌豆蚜中最完整的微小RNA集合，并为未来关于性二态性表观遗传控制的研究奠定了基础。
