Department of Veterinary Pathobiology, University of Missouri, Columbia, MO, 65211, USA.
Insect Biochem Mol Biol. 2020 Dec;127:103496. doi: 10.1016/j.ibmb.2020.103496. Epub 2020 Nov 12.
Mosquitoes are the most notorious hematophagous insects and due to their blood feeding behavior and genetic compatibility, numerous mosquito species are highly efficient vectors for certain human pathogenic parasites and viruses. The mosquito midgut is the principal organ of blood meal digestion and nutrient absorption. It is also the initial site of infection with blood meal acquired parasites and viruses. We conducted an analysis based on single-nucleus RNA sequencing (snRNA-Seq) to assess the cellular diversity of the midgut and how individual cells respond to blood meal ingestion to facilitate its digestion. Our study revealed the presence of 20 distinguishable cell-type clusters in the female midgut of Aedes aegypti. The identified cell types included intestinal stem cells (ISC), enteroblasts (EB), differentiating EB (dEB), enteroendocrine cells (EE), enterocytes (EC), EC-like cells, cardia cells, and visceral muscle (VM) cells. Blood meal ingestion dramatically changed the overall midgut cell type composition, profoundly increasing the proportions of ISC and three EC/EC-like clusters. In addition, transcriptional profiles of all cell types were strongly affected while genes involved in various metabolic processes were significantly upregulated. Our study provides a basis for further physiological and molecular studies on blood digestion, nutrient absorption, and cellular homeostasis in the mosquito midgut.
蚊子是最臭名昭著的吸血昆虫，由于它们的吸血行为和遗传相容性，许多蚊子物种是某些人类致病寄生虫和病毒的高效传播媒介。蚊子的中肠是血液消化和营养吸收的主要器官。它也是感染血液寄生虫和病毒的初始部位。我们进行了基于单细胞 RNA 测序 (snRNA-Seq) 的分析，以评估中肠的细胞多样性以及单个细胞如何响应血餐摄入以促进其消化。我们的研究揭示了埃及伊蚊雌性中肠中存在 20 个可区分的细胞类型簇。鉴定出的细胞类型包括肠干细胞 (ISC)、肠母细胞 (EB)、分化的肠母细胞 (dEB)、肠内分泌细胞 (EE)、肠细胞 (EC)、EC 样细胞、贲门细胞和内脏肌肉 (VM) 细胞。血餐摄入极大地改变了整个中肠细胞类型组成，显著增加了 ISC 和三个 EC/EC 样簇的比例。此外，所有细胞类型的转录谱都受到强烈影响，而参与各种代谢过程的基因则显著上调。我们的研究为蚊子中肠血液消化、营养吸收和细胞动态平衡的进一步生理和分子研究提供了基础。
