Rodrigues Marcela I, Takeda Agnes A S, Bravo Juliana P, Maia Ivan G
Department of Genetics, Institute of Biosciences of Botucatu, São Paulo State University Botucatu, Brazil.
Department of Physics and Biophysics, Institute of Biosciences of Botucatu, São Paulo State UniversityBotucatu, Brazil; Institute of Biotechnology, São Paulo State UniversityBotucatu, Brazil.
Front Plant Sci. 2016 Nov 30;7:1810. doi: 10.3389/fpls.2016.01810. eCollection 2016.
Plant aquaporins are water channels implicated in various physiological processes, including growth, development and adaptation to stress. In this study, the Tonoplast Intrinsic Protein (TIP) gene subfamily of Eucalyptus, an economically important woody species, was investigated and characterized. A genome-wide survey of the genome revealed the presence of eleven putative TIP genes (referred as ), which were individually assigned by phylogeny to each of the classical TIP1-5 groups. Homology modeling confirmed the presence of the two highly conserved NPA (Asn-Pro-Ala) motifs in the identified EgTIPs. Residue variations in the corresponding selectivity filters, that might reflect differences in EgTIP substrate specificity, were observed. All genes, except , were transcribed and the majority of them showed organ/tissue-enriched expression. Inspection of the promoters revealed the presence of common -regulatory elements implicated in abiotic stress and hormone responses pointing to an involvement of the identified genes in abiotic stress responses. In line with these observations, additional gene expression profiling demonstrated increased expression under polyethylene glycol-imposed osmotic stress. Overall, the results obtained suggest that these novel might be functionally implicated in eucalyptus adaptation to stress.
植物水通道蛋白是参与各种生理过程的水通道，包括生长、发育以及对胁迫的适应。在本研究中，对经济上重要的木本物种桉树的液泡膜内在蛋白（TIP）基因亚家族进行了研究和表征。对该基因组进行全基因组调查发现了11个假定的TIP基因（称为 ），通过系统发育分析将它们分别归入经典的TIP1 - 5组中的每一组。同源建模证实了在所鉴定的桉树TIP（EgTIP）中存在两个高度保守的NPA（天冬酰胺 - 脯氨酸 - 丙氨酸）基序。观察到相应选择性过滤器中的残基变异，这可能反映了EgTIP底物特异性的差异。除 外，所有 基因均被转录，并且它们中的大多数表现出器官/组织富集表达。对 启动子的检查揭示了存在与非生物胁迫和激素反应相关的常见调控元件，表明所鉴定的基因参与非生物胁迫反应。与这些观察结果一致，额外的基因表达谱显示在聚乙二醇诱导的渗透胁迫下表达增加。总体而言，所获得的结果表明这些新的 可能在桉树对胁迫的适应中具有功能作用。
