Zhang Xiao-Hong, Gao Peng, Guo Wen-Hui, Wang Ming-Jun, Yang Yong, Yin Hong, Zhang Dao-Chuan
The Key Laboratory of Zoological Systematics and Application, The International Centre for Precision Environmental Health and Governance, College of Life Sciences, Hebei University, Baoding 071002, China.
The Key Laboratory of Zoological Systematics and Application, The International Centre for Precision Environmental Health and Governance, College of Life Sciences, Hebei University, Baoding 071002, China.
Int J Biol Macromol. 2025 Aug;319(Pt 1):145300. doi: 10.1016/j.ijbiomac.2025.145300. Epub 2025 Jun 17.
Diapause is a physiological adaptation regulated by both environmental and genetic factors that occurs at specific developmental stages in each species. There are few reports on the molecular regulatory mechanisms of nymphal diapause in Locusta migratoria. As an agricultural pest, this species has evolved wings and migratory abilities, making it particularly crucial to prevent the locust from remaining in its nymphal stage or inducing diapause during this phase. Myoglianin (Myo) plays a role in regulating insect development. Nevertheless, the functional significance of the Myo remains unclear, particularly regarding its regulation of diapause. In this study, the LmMyo gene was identified and tissue-specific analyses revealed high expression levels of LmMyo in the head. Knocking out of Myo resulted in 68-72 % of locusts remaining in the nymphal stage. Additionally, the duration of the nymphal development period was significantly altered. Silencing of LmMyo altered the contents of ILP, 20E and JH, inhibited the phosphorylation of the FOXO protein, and affected cell proliferation in the different nymph development stages. Transcriptome analyses and metabolic indicators related to glucose and lipid metabolism revealed that the knockdown of Myo can alter glucose and lipid metabolism. Furthermore, the reinjection of insulin after interference with dsLmMyo can partially rescue the molting of locusts. Collectively, Myo can regulate glucose and lipid metabolism by influencing the FOXO-dependent insulin pathway, which impacts diapause. This discovery enhances our understanding of nymphal diapause and presents a promising target for the control of agricultural pests.
滞育是一种受环境和遗传因素共同调节的生理适应现象，发生在每个物种特定的发育阶段。关于飞蝗若虫滞育的分子调控机制的报道较少。作为一种农业害虫，该物种进化出了翅膀和迁徙能力，因此防止蝗虫停留在若虫阶段或在此阶段诱导滞育尤为关键。肌肉生长抑制素（Myo）在调节昆虫发育中发挥作用。然而，Myo的功能意义仍不清楚，尤其是其对滞育的调节作用。在本研究中，鉴定了LmMyo基因，组织特异性分析显示LmMyo在头部高表达。敲除Myo导致68%-72%的蝗虫停留在若虫阶段。此外，若虫发育期的持续时间也发生了显著变化。沉默LmMyo改变了ILP、20E和JH的含量，抑制了FOXO蛋白的磷酸化，并影响了不同若虫发育阶段的细胞增殖。转录组分析以及与葡萄糖和脂质代谢相关的代谢指标表明，敲低Myo会改变葡萄糖和脂质代谢。此外，干扰dsLmMyo后再注射胰岛素可部分挽救蝗虫的蜕皮。总体而言，Myo可通过影响FOXO依赖的胰岛素途径来调节葡萄糖和脂质代谢，进而影响滞育。这一发现加深了我们对若虫滞育的理解，并为农业害虫的防治提供了一个有前景的靶点。
