Yang Qun, Smagghe Guy, Staes An, Gevaert Kris, De Schutter Kristof
Laboratory of Agrozoology, Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, 9000, Ghent, Belgium.
VIB-UGent Center for Medical Biotechnology (CMB), Technologiepark-Zwijnaarde 75, 9052, Ghent, Belgium; Department of Biomolecular Medicine, Ghent University, Technologiepark-Zwijnaarde 75, 9052, Ghent, Belgium.
Insect Biochem Mol Biol. 2023 Mar;154:103918. doi: 10.1016/j.ibmb.2023.103918. Epub 2023 Feb 8.
Protein glycosylation is one of the most important post-translational modifications, modulating the properties of proteins. In insects, α-1,6-fucosyltransferase (FucT6) is an important enzyme in the glycosylation pathway, modifying the core structure of N-glycans on glycoproteins with the addition of a fucose residue. In our previous study, RNAi-mediated silencing of FucT6 in the third-instar nymphs of Nilaparvata lugens caused a failure of the ecdysis process during nymphal development, leading to high mortality. These results suggested the requirement of FucT6 during nymphal development in N. lugens. In this study, RNAi-mediated gene silencing of FucT6 in adults did not cause lethality. However, parental RNAi of FucT6 led to full failure in the hatching of eggs, and this effect was maternally mediated. Interestingly, gene expression levels of FucT6 in the eggs peaked at the katatrepsis event, where the embryo rotates 180° resulting in the head pointing towards the anterior side of the egg. Proteome analysis showed significant differences in the abundance of proteins between different embryonal developmental stages, suggesting the crucial role of FucT6 mediated core N-fucosylation in embryonal development. Therefore, correct α-1,6-fucosylation of glycoproteins is important for N. lugens during embryonic development and this study provides new insights into the role of N-glycosylation in embryogenesis in insects.
蛋白质糖基化是最重要的翻译后修饰之一,可调节蛋白质的特性。在昆虫中,α-1,6-岩藻糖基转移酶(FucT6)是糖基化途径中的一种重要酶,通过添加一个岩藻糖残基来修饰糖蛋白上N-聚糖的核心结构。在我们之前的研究中,RNA干扰介导的褐飞虱三龄若虫中FucT6沉默导致若虫发育过程中的蜕皮过程失败,从而导致高死亡率。这些结果表明褐飞虱若虫发育过程中需要FucT6。在本研究中,RNA干扰介导的成虫中FucT6基因沉默并未导致致死性。然而,FucT6的亲代RNA干扰导致卵完全无法孵化,且这种效应是由母体介导的。有趣的是,卵中FucT6的基因表达水平在胚胎反转事件时达到峰值,此时胚胎旋转180°,导致头部指向卵的前侧。蛋白质组分析表明,不同胚胎发育阶段之间蛋白质丰度存在显著差异,这表明FucT6介导的核心N-岩藻糖基化在胚胎发育中起关键作用。因此,糖蛋白的正确α-1,6-岩藻糖基化对褐飞虱胚胎发育很重要,本研究为N-糖基化在昆虫胚胎发生中的作用提供了新的见解。