Page 86 - 《广西植物》2020年第8期
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8 期                    王赛赛等: 三种植物线粒体基因低温差异表达比较分析                                          1 1 4 1

       tered through blast against the mitochondria genomes that was downloaded from the NCBI database. Promoter analysis
       was performed through PlantCARE online website and the mega software was used to phylogenetic tree construction. The
       results were as follows: In totalꎬ there were 2ꎬ 24 and 15 DEGs were found in Saussurea involucrataꎬ Arabidopsis
       thaliana and Lycopersicon esculentumꎬ and these genes were mainly focused on mitochondrial ribosomal and electron
       transfer chain complex subunitsꎻ A few genes were seemed to relate to the cold adaptation that the expression level was
       positive to the ability of cold tolerance of the three plantsꎬ especially for the NAD1 and NAD5 geneꎻ Through cluster
       analysis of expression patternsꎬ Saussurea involucrata and Arabidopsis thaliana were more similar in genes expression
       mode than Lycopersicon esculentumꎬ and the expression mode of different genes had a quite difference between different
       plantsꎻ Further analysis on the conserved motif sequence of these genesꎬ the sequences of Saussurea involucrata showed
       more close relationship with the alpine plants such as Climacium dendroides and Anomodon minor than the other composi ̄
       tae plants. In generalꎬ the mitochondrial genes had a quite difference on the sequence of conserved motif and expression
       mode under the cold condition between the Arabidopsis thalianaꎬ Lycopersicon esculentum and Saussurea involucrata. It
       was concluded that the mitochondria genes and its expressional regulation could be implicated in the cold adaptation of
       plants.
       Key words: low temperature toleranceꎬ plantsꎬ mitochondrial geneꎬ expression mode


       植物线粒体通过氧化磷酸化提供生命活动所                           oxidaseꎬ AOX)、 解 偶 联 蛋 白 ( uncoupling proteinꎬ
   需的各种能量ꎬ在光呼吸代谢、C4 植物的光合作                           UCP)等的表达水平受到冷或热胁迫的影响ꎬ预示

   用和景天酸代谢(Picault et al.ꎬ 2004) 等途径中发               着这些蛋白可能参与了植物对温度胁迫的响应过
   挥着重要作用ꎮ 线粒体的主要功能是进行三羧酸                            程(Yin et al.ꎬ 2009ꎻ Qin et al.ꎬ 2009ꎻ Tan et al.ꎬ
   循环ꎬ通过电子传递链及氧化磷酸化合成 ATPꎬ这                          2012)ꎮ 但是ꎬ植物线粒体中存在有多条电子传递
   里是物质彻底氧化分解的场所ꎬ为细胞内的各种                             途径ꎬ低温胁迫对不同植物线粒体呼吸链的具体
   生命活动提供能量ꎮ 此外ꎬ线粒体还与细胞内众                            伤害位点也会不同( 刘美君等ꎬ 2014)ꎮ 如在对半

   多代谢过程相关ꎬ如参与细胞内信号转导ꎬ调节细                            耐寒植物豌豆(Pisum sativum)的蛋白组研究中ꎬ低
   胞内氧化还原电位ꎬ调控基因表达、细胞凋亡等                             温对其电子传递链复合物的影响较小ꎬ主要影响
   (Millar et al.ꎬ 2011)ꎮ 线粒体在植物响应逆境胁                的是线粒体中 AOX 和 UCP 的丰度( Taylor et al.ꎬ
   迫中有重要作用ꎬ在逆境胁迫下它们的形态结构                             2009)ꎻ在对耐寒植物高山离子芥( Chorispora bun ̄
   和生理功能会发生明显的变化ꎬ在一定程度上可                             geana)研究中ꎬ低温对其线粒体的影响又出现不
   作为表征植物对逆境条件耐受性的依据( 周宇飞                            同ꎬ其线粒体中 AOX 和 UCP 含量变化较小ꎬ但呼
   等ꎬ 2013)ꎮ 逆 境 胁 迫 会 引 起 呼 吸 代 谢 的 紊 乱             吸链复合体的变化较高( 常建锋ꎬ 2007)ꎮ 这表明

   ( Vanhoudt et al.ꎬ 2011ꎻ Tulah & Birch ̄Machinꎬ    不同植物线粒体在应对低温胁迫时的响应机制有
   2013)ꎬ造成活性氧的积累ꎬ过剩的 ROS 会诱导或                       所不同ꎬ其响应机制可能与其低温耐受性之间存
   加剧膜脂过氧化程度ꎬ导致脂质过氧化物水平迅                             在某种关联ꎮ
   速提高(Sairam & Srivastavaꎬ 2002)ꎬ主要体现在线                 本研究主要根据雪莲、拟南芥和番茄三种不
   粒体膜和膜蛋白的损伤、线粒体蛋白质损伤、线粒                            同低温耐受性植物的低温转录组ꎬ筛选并比较其

   体 DNA 损伤等(Rachel et al.ꎬ 2005ꎻ Foyer & Noc ̄       线粒体基因表达差异ꎬ来探索植物线粒体低温表
   torꎬ 2010ꎻ 马晓蕾等ꎬ 2013)ꎮ 通过对冷胁迫下植                  达模式与低温耐受性之间的关系ꎮ 通过对低温条
   物线粒体蛋白组的研究发现ꎬ一些线粒体蛋白如                             件下ꎬ三种不同低温耐受性植物线粒体基因表达
   线粒体电子传递链( mitochondrial electron transport        差异比较和不同低温耐受性植物间线粒体基因进
   chainꎬ mETC)复合物 I-V、交替氧化酶( alternative            化关系的对比ꎬ来分析不同低温耐受性植物间低
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