Mosquito (Aedes aegypti) aquaporin, present in tracheolar cells, transports water, not glycerol, and forms orthogonal arrays in Xenopus oocyte membranes
Mosquito (Aedes aegypti) aquaporin, present in tracheolar cells, transports water, not glycerol, and forms orthogonal arrays in Xenopus oocyte membranes
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DOI：
10.1046/j.1432-1033.2003.03389.x
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发表时间：
2003-02-01
期刊：
影响因子：
--
通讯作者：
Pietrantonio, PV
中科院分区：
文献类型：
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作者：
Duchesne, L;Hubert, JF;Pietrantonio, PV
先前的结果表明，编码假定的水通道蛋白（AQP）（GenBank 登录号 AF218314）的 mRNA 存在于与雌性埃及伊蚊马尔皮基小管相关的气管细胞中。在这项研究中，免疫组织化学在气管细胞中检测到了 Aea AQP 蛋白，表明它参与了呼吸系统中的水运动。当Aea AQP在非洲爪蟾卵母细胞中表达时，渗透水渗透率从15 x 10(-6)增加到150 x 10(-6) m.s(-1)，而汞离子抑制该渗透率。没有观察到甘油或其他溶质的渗透性。根据密度梯度上的速度离心推断，卵母细胞中表达的 Aea AQP 作为同四聚体溶解在非变性洗涤剂中。 MIP（主要内在蛋白）家族序列的系统发育分析表明，Aea AQP 与其他天然正交阵列形成蛋白聚类。通过 Aea AQP 卵母细胞膜的冷冻断裂分析检测特定的正交阵列。我们的结论是，在埃及伊蚊的气管细胞中，Aea AQP 可能是一种高透水性的同源四聚体 MIP，其本身可以形成 2D 晶体。
Previous results showed that mRNA encoding a putative aquaporin (AQP) (GenBank accession number AF218314) is present in the tracheolar cells associated with female Aedes aegypti Malpighian tubules. In this study, immunohistochemistry detected the protein, Aea AQP, also in tracheolar cells, suggesting its involvement in water movement in the respiratory system. When expressed in Xenopus oocytes, Aea AQP increased the osmotic water permeability from 15 x 10(-6) to 150 x 10(-6) m.s(-1), which was inhibited by mercury ions. No permeability to glycerol or other solute was observed. Aea AQP expressed in oocytes was solubilized as a homotetramer in nondenaturing detergent as deduced from velocity centrifugation on density gradients. Phylogenetic analysis of MIP (major intrinsic protein) family sequences shows that Aea AQP clusters with other native orthogonal array forming proteins. Specific orthogonal arrays were detected by freeze-fracture analysis of Aea AQP oocyte membranes. We conclude that, in tracheolar cells of A. aegypti , Aea AQP is probably a highly water-permeable homotetrameric MIP which natively can form 2D crystals.