Grohme Markus A, Mali Brahim, Wełnicz Weronika, Michel Stephanie, Schill Ralph O, Frohme Marcus
Molecular Biotechnology and Functional Genomics, Technical University of Applied Sciences Wildau, Wildau, Germany.
Bioinform Biol Insights. 2013 May 26;7:153-65. doi: 10.4137/BBI.S11497. Print 2013.
Limno-terrestrial tardigrades are small invertebrates that are subjected to periodic drought of their micro-environment. They have evolved to cope with these unfavorable conditions by anhydrobiosis, an ametabolic state of low cellular water. During drying and rehydration, tardigrades go through drastic changes in cellular water content. By our transcriptome sequencing effort of the limno-terrestrial tardigrade Milnesium tardigradum and by a combination of cloning and targeted sequence assembly, we identified transcripts encoding eleven putative aquaporins. Analysis of these sequences proposed 2 classical aquaporins, 8 aquaglyceroporins and a single potentially intracellular unorthodox aquaporin. Using quantitative real-time PCR we analyzed aquaporin transcript expression in the anhydrobiotic context. We have identified additional unorthodox aquaporins in various insect genomes and have identified a novel common conserved structural feature in these proteins. Analysis of the genomic organization of insect aquaporin genes revealed several conserved gene clusters.
淡水陆生缓步动物是小型无脊椎动物，其微环境会经历周期性干旱。它们已经进化出通过隐生状态来应对这些不利条件，隐生是一种细胞水分含量低的无代谢状态。在干燥和复水过程中，缓步动物的细胞含水量会发生剧烈变化。通过我们对淡水陆生缓步动物米尔恩氏熊虫（Milnesium tardigradum）的转录组测序工作，并结合克隆和靶向序列组装，我们鉴定出了编码11种假定水通道蛋白的转录本。对这些序列的分析表明有2种经典水通道蛋白、8种水甘油通道蛋白和1种可能位于细胞内的非传统水通道蛋白。我们使用定量实时PCR分析了在隐生环境下水通道蛋白转录本的表达。我们在各种昆虫基因组中鉴定出了其他非传统水通道蛋白，并在这些蛋白质中发现了一种新的共同保守结构特征。对昆虫水通道蛋白基因的基因组组织分析揭示了几个保守的基因簇。
