Tian Feng-Xia, Zang Jian-Lei, Wang Tan, Xie Yu-Li, Zhang Jin, Hu Jian-Jun
College of Life Science and Technology, Nanyang Normal University, Nanyang, Henan, 473061, China; State Key Laboratory of Tree Genetics and Breeding, Key Laboratory of Tree Breeding and Cultivation of the State Forestry Administration, Research Institute of Forestry, Chinese Academy of Forestry, Beijing, 100091, China.
State Key Laboratory of Tree Genetics and Breeding, Key Laboratory of Tree Breeding and Cultivation of the State Forestry Administration, Research Institute of Forestry, Chinese Academy of Forestry, Beijing, 100091, China; Research Institute of Wood Industry, Chinese Academy of Forestry, Beijing, 100091, China.
PLoS One. 2015 Apr 24;10(4):e0124669. doi: 10.1371/journal.pone.0124669. eCollection 2015.
Aldehyde dehydrogenases (ALDHs) constitute a superfamily of NAD(P)+-dependent enzymes that catalyze the irreversible oxidation of a wide range of reactive aldehydes to their corresponding nontoxic carboxylic acids. ALDHs have been studied in many organisms from bacteria to mammals; however, no systematic analyses incorporating genome organization, gene structure, expression profiles, and cis-acting elements have been conducted in the model tree species Populus trichocarpa thus far. In this study, a comprehensive analysis of the Populus ALDH gene superfamily was performed. A total of 26 Populus ALDH genes were found to be distributed across 12 chromosomes. Genomic organization analysis indicated that purifying selection may have played a pivotal role in the retention and maintenance of PtALDH gene families. The exon-intron organizations of PtALDHs were highly conserved within the same family, suggesting that the members of the same family also may have conserved functionalities. Microarray data and qRT-PCR analysis indicated that most PtALDHs had distinct tissue-specific expression patterns. The specificity of cis-acting elements in the promoter regions of the PtALDHs and the divergence of expression patterns between nine paralogous PtALDH gene pairs suggested that gene duplications may have freed the duplicate genes from the functional constraints. The expression levels of some ALDHs were up- or down-regulated by various abiotic stresses, implying that the products of these genes may be involved in the adaptation of Populus to abiotic stresses. Overall, the data obtained from our investigation contribute to a better understanding of the complexity of the Populus ALDH gene superfamily and provide insights into the function and evolution of ALDH gene families in vascular plants.
醛脱氢酶（ALDHs）构成了一个依赖NAD(P)+的酶超家族，该家族催化多种活性醛不可逆地氧化为相应的无毒羧酸。人们已经在从细菌到哺乳动物的许多生物体中对ALDHs进行了研究；然而，迄今为止，尚未在模式树种毛果杨中进行过结合基因组组织、基因结构、表达谱和顺式作用元件的系统分析。在本研究中，对毛果杨ALDH基因超家族进行了全面分析。共发现26个毛果杨ALDH基因分布在12条染色体上。基因组组织分析表明，纯化选择可能在PtALDH基因家族的保留和维持中起关键作用。PtALDHs的外显子-内含子组织在同一家族内高度保守，这表明同一家族的成员可能也具有保守的功能。微阵列数据和qRT-PCR分析表明，大多数PtALDHs具有明显的组织特异性表达模式。PtALDHs启动子区域顺式作用元件的特异性以及9对旁系同源PtALDH基因对之间表达模式的差异表明，基因复制可能使复制基因摆脱了功能限制。一些ALDHs的表达水平受到各种非生物胁迫的上调或下调，这意味着这些基因的产物可能参与了毛果杨对非生物胁迫的适应。总体而言，我们研究获得的数据有助于更好地理解毛果杨ALDH基因超家族的复杂性，并为维管植物中ALDH基因家族的功能和进化提供见解。
