A de novo transcriptome of the Malpighian tubules in non-blood-fed and blood-fed Asian tiger mosquitoes Aedes albopictus: insights into diuresis, detoxification, and blood meal processing.
A de novo transcriptome of the Malpighian tubules in non-blood-fed and blood-fed Asian tiger mosquitoes Aedes albopictus: insights into diuresis, detoxification, and blood meal processing.
复制标题
作者：
Esquivel CJ;Cassone BJ;Piermarini PM
背景。在成年雌蚊中，肾（马尔比氏）小管在餐后利尿中起着重要作用，它在吸血后从蚊子的血淋巴中去除多余的离子和水。餐后利尿后，马氏小管在血餐加工过程中所起的作用尚不清楚。方法。研究人员对成年雌性亚洲虎蚊（白纹伊蚊）进行了新一代测序（配对端RNA测序）和生理/生化分析，以获得马尔比氏小管的分子和功能见解，以及它们如何在血液摄取后3-24小时参与血粉处理。结果/讨论。利用RNA测序技术，对非血供（NBF）和血供（BF）蚊子马尔比氏小管的首个从头转录组进行了测序和组装。共鉴定出8232份非冗余转录本。NBF蚊子马尔比氏小管的特征是表达与活跃的经皮液分泌/利尿相关的转录物（如离子转运体、水通道、v型H+- atp酶亚基）、外源解毒（如细胞色素P450单加氧酶、谷胱甘肽s转移酶、atp结合盒转运体）和嘌呤代谢（如黄嘌呤脱氢酶）。我们还在蚊子马尔比氏小管中检测到了编码钠钙交换器、G蛋白偶联受体和分离连接蛋白的转录本的表达，这些转录本之前没有在蚊子马尔比氏小管中描述过。在血食后24小时内，与活跃的上皮液分泌/利尿相关的转录本普遍下调，而与外源解毒和嘌呤分解代谢相关的转录本则普遍上调，这表明马尔比氏小管分子资源从利尿到解毒的再投资。分别对蚊子和分离的马尔比氏小管进行了生理和生化分析，以证实转录组学变化与功能后果有关。特别是，体内利尿试验表明，成年雌蚊在吸血后24小时内利尿能力下降。此外，分离的马尔比氏小管的生化分析显示，在血餐后24小时内，谷胱甘肽s -转移酶活性和尿酸（嘌呤分解代谢的最终产物）的积累增加。我们的数据为烹饪蚊子马尔比氏小管的分子生理学提供了新的见解，并揭示了开发破坏蚊子肾功能的化学和/或基因沉默杀虫剂的潜在重要分子靶点。
Background. In adult female mosquitoes, the renal (Malpighian) tubules play an important role in the post-prandial diuresis, which removes excess ions and water from the hemolymph of mosquitoes following a blood meal. After the post-prandial diuresis, the roles that Malpighian tubules play in the processing of blood meals are not well described. Methods. We used a combination of next-generation sequencing (paired-end RNA sequencing) and physiological/biochemical assays in adult female Asian tiger mosquitoes (Aedes albopictus) to generate molecular and functional insights into the Malpighian tubules and how they may contribute to blood meal processing (3–24 h after blood ingestion). Results/Discussion. Using RNA sequencing, we sequenced and assembled the first de novo transcriptome of Malpighian tubules from non-blood-fed (NBF) and blood-fed (BF) mosquitoes. We identified a total of 8,232 non-redundant transcripts. The Malpighian tubules of NBF mosquitoes were characterized by the expression of transcripts associated with active transepithelial fluid secretion/diuresis (e.g., ion transporters, water channels, V-type H+-ATPase subunits), xenobiotic detoxification (e.g., cytochrome P450 monoxygenases, glutathione S-transferases, ATP-binding cassette transporters), and purine metabolism (e.g., xanthine dehydrogenase). We also detected the expression of transcripts encoding sodium calcium exchangers, G protein coupled-receptors, and septate junctional proteins not previously described in mosquito Malpighian tubules. Within 24 h after a blood meal, transcripts associated with active transepithelial fluid secretion/diuresis exhibited a general downregulation, whereas those associated with xenobiotic detoxification and purine catabolism exhibited a general upregulation, suggesting a reinvestment of the Malpighian tubules’ molecular resources from diuresis to detoxification. Physiological and biochemical assays were conducted in mosquitoes and isolated Malpighian tubules, respectively, to confirm that the transcriptomic changes were associated with functional consequences. In particular, in vivo diuresis assays demonstrated that adult female mosquitoes have a reduced diuretic capacity within 24 h after a blood meal. Moreover, biochemical assays in isolated Malpighian tubules showed an increase in glutathione S-transferase activity and the accumulation of uric acid (an end product of purine catabolism) within 24 h after a blood meal. Our data provide new insights into the molecular physiology of Malpighian tubules in culicine mosquitoes and reveal potentially important molecular targets for the development of chemical and/or gene-silencing insecticides that would disrupt renal function in mosquitoes.