Van Lommel Joachim, Holtof Michiel, Tilleman Laurentijn, Cools Dorien, Vansteenkiste Seppe, Polgun Daria, Verdonck Rik, Van Nieuwerburgh Filip, Vanden Broeck Jozef
Molecular Developmental Physiology and Signal Transduction Lab, Department of Biology, University of Leuven, Leuven, Belgium.
NXTGNT, Department of Pharmaceutics, Ghent University, Ghent, Belgium.
Front Physiol. 2023 Aug 10;14:1232545. doi: 10.3389/fphys.2023.1232545. eCollection 2023.
The digestive tract constitutes an important interface between an animal's internal and external environment. In insects, available gut transcriptome studies are mostly exploratory or look at changes upon infection or upon exposure to xenobiotics, mainly performed in species belonging to holometabolan orders, such as Diptera, Lepidoptera or Coleoptera. By contrast, studies focusing on gene expression changes after food uptake and during digestion are underrepresented. We have therefore compared the gene expression profiles in the midgut of the desert locust, , between three different time points after feeding, i.e., 24 h (no active digestion), 10 min (the initial stage of feeding), and 2 h (active food digestion). The observed gene expression profiles were consistent with the polyphagous herbivorous lifestyle of this hemimetabolan (orthopteran) species. Our study reveals the upregulation of 576 genes 2 h post-feeding. These are mostly predicted to be associated with digestive physiology, such as genes encoding putative digestive enzymes or nutrient transporters, as well as genes putatively involved in immunity or in xenobiotic metabolism. The 10 min time point represented an intermediate condition, suggesting that the midgut can react rapidly at the transcriptional level to the presence of food. Additionally, our study demonstrated the critical importance of two transcripts that exhibited a significant upregulation 2 h post-feeding: the vacuolar-type H(+)-ATPase and the sterol transporter Niemann-Pick 1b protein, which upon RNAi-induced knockdown resulted in a marked increase in mortality. Their vital role and accessibility via the midgut lumen may make the encoded proteins promising insecticidal target candidates, considering that the desert locust is infamous for its huge migrating swarms that can devastate the agricultural production in large areas of Northern Africa, the Middle East, and South Asia. In conclusion, the transcriptome datasets presented here will provide a useful and promising resource for studying the midgut physiology of , a socio-economically important pest species.
消化道构成了动物内部和外部环境之间的重要界面。在昆虫中，现有的肠道转录组研究大多是探索性的，或者关注感染后或接触外源性物质后的变化，主要在属于全变态目（如双翅目、鳞翅目或鞘翅目）的物种中进行。相比之下，关注食物摄取后和消化过程中基因表达变化的研究较少。因此，我们比较了沙漠蝗中肠在进食后三个不同时间点（即24小时（无活跃消化）、10分钟（进食初始阶段）和2小时（活跃食物消化））的基因表达谱。观察到的基因表达谱与这种半变态（直翅目）物种的多食性草食性生活方式一致。我们的研究揭示了进食后2小时576个基因的上调。这些基因大多预计与消化生理相关，例如编码假定消化酶或营养转运蛋白的基因，以及假定参与免疫或外源性物质代谢的基因。10分钟这个时间点代表了一种中间状态，表明中肠能够在转录水平对食物的存在迅速做出反应。此外，我们的研究证明了两个转录本的关键重要性，它们在进食后2小时表现出显著上调：液泡型H(+)-ATP酶和甾醇转运蛋白尼曼-皮克1b蛋白，RNA干扰诱导的敲低导致死亡率显著增加。考虑到沙漠蝗因其庞大的迁飞群体而臭名昭著，这些群体能够破坏北非、中东和南亚大片地区的农业生产，它们的重要作用以及通过中肠腔的可及性可能使编码的蛋白质成为有前景的杀虫靶标候选物。总之，这里呈现的转录组数据集将为研究这种具有社会经济重要性的害虫物种沙漠蝗的中肠生理学提供有用且有前景的资源。
