Jiangsu Key Laboratory for Biodiversity and Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing, China.
Insect Mol Biol. 2019 Apr;28(2):208-221. doi: 10.1111/imb.12539. Epub 2018 Oct 21.
The microRNA miR-8-3p is conserved among insects and closely involved in development and immunity, but its functions in vivo are unexplored in the red flour beetle, Tribolium castaneum. Here, we show that miR-8-3p was highly expressed in late larva and early adult stages, as determined by quantitative real-time PCR. It was enriched in the fat body and cuticle in late larval tissues and abundant in the head and cuticle in early adult tissues, indicating this microRNA plays important roles during T. castaneum development. Specific inhibition of miR-8-3p in late larvae led to metamorphosis defects in the development of wings, eyes, legs and embryo. Moreover, a series of genes related to organism development were identified as miR-8-3p targets by computational prediction and microRNA-messenger RNA interaction validation, including Wingless, Eyg, Fpps and Sema-1a. These genes were critical for the regulation of the larva-to-adult transition. Eyg, as a functional target of miR-8-3p, participates in eye development, which was further confirmed by luciferase assay and loss-of-function analyses. In brief, miR-8-3p is broadly involved in the development of wings, eyes and legs through its target genes and has extensive regulatory roles during T. castaneum development.
miR-8-3p 是一种在昆虫中保守的 microRNA，与发育和免疫密切相关，但在赤拟谷盗（Tribolium castaneum）中，其体内功能尚未被探索。在这里，我们通过定量实时 PCR 显示，miR-8-3p 在晚期幼虫和早期成虫阶段高度表达。在晚期幼虫组织中，它在脂肪体和表皮中富集，在早期成虫组织中在头部和表皮中丰富，表明这种 microRNA 在 T. castaneum 的发育过程中发挥重要作用。在晚期幼虫中特异性抑制 miR-8-3p 导致翅膀、眼睛、腿和胚胎的发育出现变态缺陷。此外，通过计算预测和 microRNA-messenger RNA 相互作用验证，确定了一系列与生物体发育相关的基因是 miR-8-3p 的靶标，包括 Wingless、Eyg、Fpps 和 Sema-1a。这些基因对于幼虫到成虫的过渡的调节至关重要。Eyg 作为 miR-8-3p 的功能靶标，参与眼睛的发育，这进一步通过荧光素酶测定和功能丧失分析得到证实。总之，miR-8-3p 通过其靶基因广泛参与翅膀、眼睛和腿的发育，并在 T. castaneum 的发育过程中具有广泛的调节作用。
