Abstract:
Mosquitoes (Anopheles sinensis), widely geographically distributed in Asia including China, are the primary vector of the malaria parasite Plasmodium vivax and other parasitic diseases such as Malayan filariasis. An. sinensis can survive through low winter temperatures. Aquaporin channels are found in all life forms, where they facilitate environmental adaptation by allowing rapid trans-cellular movement of water (classical aquaporins) or water and solutes such as glycerol (aquaglyceroporins). Here, we identified and characterized 2 aquaporin (AQP) homologs in An. sinensis: AsAQP2 (An. sinensis aquaglyceroporin) and AsAQP4 (An. sinensis aquaporin). When expressed in frog (Xenopus laevis) oocytes, AsAQP2 transported water, glycerol, and urea; AsAQP4 transported only water. Water permeation through AsAQP2 and AsAQP4 was inhibited by mercuric chloride. AsAQP2 expression was slightly higher in adult female mosquitoes than in males, and AsAQP4 expression was significantly higher in adult males. The 2 AsAQPs were highly expressed in Malpighian tubules and midgut. AsAQP2 and AsAQP4 expression was up-regulated by blood feeding compared with sugar feeding. At freezing point (0 °C), the AsAQP4 expression level increased and An. sinensis survival time reduced compared with those at normal temperature (26 °C). At low temperature (8 °C), the AsAQP2 and AsAQP4 expression levels decreased and survival time was significantly longer compared with those at 26 °C. These results suggest that AsAQP2 and AsAQP4 have roles in water homeostasis during blood digestion and in low temperature adaptation of A. sinensis. Together, our results show that the 2 AQPs are important for mosquito diuresis after blood feeding and when exposed to low temperatures.
摘要:
蚊子(中华按蚊),广泛的地理分布在亚洲,包括中国,是疟疾寄生虫间日疟原虫和其他寄生虫病如马来亚丝虫病的主要媒介。A.中国可以在冬季低温下生存。水通道存在于所有生命形式中,它们通过允许水(经典的水通道蛋白)或水和诸如甘油(aquaglyceroporoins)的溶质的快速跨细胞运动来促进环境适应。这里,我们在An中鉴定并表征了2个水通道蛋白(AQP)同源物。中华:AsAQP2(An。中国水甘油)和AsAQP4(An。中华水通道蛋白)。当在青蛙(非洲爪狼)卵母细胞中表达时,AsAQP2输送水,甘油,和尿素;AsAQP4只输送水。氯化汞抑制了通过AsAQP2和AsAQP4的水渗透。AsAQP2的表达在成年雌性蚊子中略高于雄性蚊子,AsAQP4在成年男性中表达显著增高。2个AsAQPs在马氏小管和中肠中高表达。与糖饲喂相比,血液饲喂可上调AsAQP2和AsAQP4的表达。在冰点(0°C),AsAQP4表达水平升高和An.与常温(26°C)相比,中华民国的存活时间减少。在低温(8°C)下,与26°C相比,AsAQP2和AsAQP4表达水平降低,存活时间明显延长。这些结果表明,AsAQP2和AsAQP4在血液消化过程中的水稳态和低温适应中具有作用。一起,我们的结果表明,2AQP对血液喂养后和暴露于低温时的蚊子利尿很重要。