Dmitriev Alexey A, Krasnov George S, Rozhmina Tatiana A, Kishlyan Natalya V, Zyablitsin Alexander V, Sadritdinova Asiya F, Snezhkina Anastasiya V, Fedorova Maria S, Yurkevich Olga Y, Muravenko Olga V, Bolsheva Nadezhda L, Kudryavtseva Anna V, Melnikova Nataliya V
Engelhardt Institute of Molecular Biology, Russian Academy of Sciences Moscow, Russia.
Engelhardt Institute of Molecular Biology, Russian Academy of SciencesMoscow, Russia; All-Russian Research Institute for FlaxTorzhok, Russia.
Front Plant Sci. 2016 Dec 21;7:1920. doi: 10.3389/fpls.2016.01920. eCollection 2016.
About 30% of the world's ice-free land area is occupied by acid soils. In soils with pH below 5, aluminum (Al) releases to the soil solution, and becomes highly toxic for plants. Therefore, breeding of varieties that are resistant to Al is needed. Flax ( L.) is grown worldwide for fiber and seed production. Al toxicity in acid soils is a serious problem for flax cultivation. However, very little is known about mechanisms of flax resistance to Al and the genetics of this resistance. In the present work, we sequenced 16 transcriptomes of flax cultivars resistant (Hermes and TMP1919) and sensitive (Lira and Orshanskiy) to Al, which were exposed to control conditions and aluminum treatment for 4, 12, and 24 h. In total, 44.9-63.3 million paired-end 100-nucleotide reads were generated for each sequencing library. Based on the obtained high-throughput sequencing data, genes with differential expression under aluminum exposure were revealed in flax. The majority of the top 50 up-regulated genes were involved in transmembrane transport and transporter activity in both the Al-resistant and Al-sensitive cultivars. However, genes encoding proteins with glutathione transferase and UDP-glycosyltransferase activity were in the top 50 up-regulated genes only in the flax cultivars resistant to aluminum. For qPCR analysis in extended sampling, two UDP-glycosyltransferases (UGTs), and three glutathione S-transferases (GSTs) were selected. The general trend of alterations in the expression of the examined genes was the up-regulation under Al stress, especially after 4 h of Al exposure. Moreover, in the flax cultivars resistant to aluminum, the increase in expression was more pronounced than that in the sensitive cultivars. We speculate that the defense against the Al toxicity GST antioxidant activity is the probable mechanism of the response of flax plants to aluminum stress. We also suggest that UGTs could be involved in cell wall modification and protection from reactive oxygen species (ROS) in response to Al stress in . Thus, GSTs and UGTs, probably, play an important role in the response of flax to Al detoxification of ROS and cell wall modification.
世界上约30%的无冰陆地面积被酸性土壤占据。在pH值低于5的土壤中，铝（Al）会释放到土壤溶液中，对植物产生高毒性。因此，需要培育抗铝品种。亚麻（L.）在全球范围内种植用于纤维和种子生产。酸性土壤中的铝毒性是亚麻种植面临的一个严重问题。然而，关于亚麻抗铝机制及其抗性遗传学的了解却非常少。在本研究中，我们对亚麻抗铝品种（Hermes和TMP1919）和铝敏感品种（Lira和Orshanskiy）的16个转录组进行了测序，这些品种分别在对照条件下以及铝处理4、12和24小时后进行测序。每个测序文库共产生了4490万至6330万对末端100个核苷酸的reads。基于获得的高通量测序数据，揭示了亚麻在铝暴露下差异表达的基因。在抗铝和铝敏感品种中，上调的前50个基因中的大多数都参与跨膜运输和转运蛋白活性。然而，编码具有谷胱甘肽转移酶和UDP-糖基转移酶活性蛋白质的基因仅在抗铝亚麻品种的上调前50个基因中出现。为了进行扩展采样的qPCR分析，选择了两个UDP-糖基转移酶（UGT）和三个谷胱甘肽S-转移酶（GST）。所检测基因表达变化的总体趋势是在铝胁迫下上调，尤其是在铝暴露4小时后。此外，在抗铝亚麻品种中，表达的增加比敏感品种更为明显。我们推测，谷胱甘肽转移酶抗氧化活性对铝毒性的防御可能是亚麻植株对铝胁迫的响应机制。我们还认为，UDP-糖基转移酶可能参与细胞壁修饰以及在亚麻中响应铝胁迫时免受活性氧（ROS）的侵害。因此，谷胱甘肽转移酶和UDP-糖基转移酶可能在亚麻对铝的响应中发挥重要作用——活性氧解毒和细胞壁修饰。
