Vector Biology Section, Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, Bethesda, MD, USA.
Tick-Pathogen Transmission Unit, Laboratory of Bacteriology, National Institute of Allergy and Infectious Diseases, Hamilton, MT, USA.
BMC Genomics. 2024 Oct 24;25(1):996. doi: 10.1186/s12864-024-10905-y.
Female ticks remain attached to their host for multiple days to complete a blood meal. This prolonged feeding period is accompanied by a significant increase in the tick's size and body weight, paralleled by noteworthy changes to the tick midgut. While the midgut is recognized for its established role in blood storage and processing, its importance extends to playing a crucial role in the acquisition, survival, and proliferation of pathogens. Despite this, our overall understanding of tick midgut biology is limited.
Our transcriptome analysis identified 15,599 putative DNA coding sequences (CDS), which were classified into 26 functional groups. Dimensional and differential expression analyses revealed four primary transcriptional profiles corresponding to unfed, slow-feeding, transitory (from slow- to rapid-feeding), and rapid-feeding stages. Additionally, comparing the current dataset with previously deposited transcriptome from other tick species allowed the identification of commonly expressed transcripts across different feeding stages.
Our findings provide a detailed temporal resolution of numerous metabolic pathways in the midgut of A. americanum adult females throughout the feeding process, highlighting the dynamic transcriptional regulation of the tick's midgut as feeding progresses. Furthermore, we identified conserved transcripts across three different tick species that exhibit similar expression patterns. This knowledge not only enhances our understanding of the physiological processes within the tick midgut but also opens up potential avenues for developing control methods that target multiple tick species.
雌性蜱虫会在宿主身上停留数天以完成一次血餐。在这个延长的进食过程中，蜱虫的体积和体重显著增加，同时蜱虫的中肠也发生了显著变化。虽然中肠因其在血液储存和处理方面的既定作用而广为人知，但它在病原体的获取、存活和增殖中也起着至关重要的作用。尽管如此，我们对蜱虫中肠生物学的整体理解仍然有限。
我们的转录组分析鉴定出了 15599 个可能的 DNA 编码序列（CDS），它们被分为 26 个功能组。维度和差异表达分析揭示了四个主要的转录谱，分别对应于未进食、缓慢进食、过渡（从缓慢进食到快速进食）和快速进食阶段。此外，将当前数据集与其他蜱种先前的转录组数据进行比较，确定了不同进食阶段共同表达的转录本。
我们的研究结果为 A. americanum 成年雌蜱在整个进食过程中中肠内许多代谢途径的详细时间分辨率提供了依据，突出了随着进食的进行，蜱虫中肠的动态转录调控。此外，我们在三个不同的蜱种中鉴定出了保守的转录本，它们表现出相似的表达模式。这些知识不仅增强了我们对蜱虫中肠内生理过程的理解，还为开发针对多种蜱种的控制方法开辟了潜在途径。
