Bioinformatic and functional characterization of the basic peroxidase 72 from Arabidopsis thaliana involved in lignin biosynthesis
Bioinformatic and functional characterization of the basic peroxidase 72 from Arabidopsis thaliana involved in lignin biosynthesis
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DOI：
10.1007/s00425-013-1865-5
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发表时间：
2013-06-01
期刊：
影响因子：
4.3
通讯作者：
Miguel Zapata, Jose
中科院分区：
文献类型：
--
作者：
Herrero, Joaquin;Fernandez-Perez, Francisco;Miguel Zapata, Jose
木质素是由三种羟基肉桂醇（对香豆醇、松柏醇和芥子醇）在过氧化物酶介导的反应中氧化聚合而得。其中最重要的是来自百日菊的阳离子过氧化物酶（ZePrx），这种酶被认为是负责这种植物中木质化的最后一步。文献证据表明，拟南芥过氧化物酶72（AtPrx 72），这是同源的ZePrx，可能有一个重要的作用，在木质化。出于这个原因，我们进行了生物信息学，组织化学，光合作用，和表型和木质素组成分析的拟南芥AtPrx 72基因敲除突变体的特征的影响，由于缺乏这种过氧化物酶的表达，从植物生理学方面，如血管发育，木质化，光合作用的目的。计算机模拟分析表明AtPrx 72和ZePrx之间的高度同源性，细胞壁定位和可能的AtPrx 72翻译的最佳水平。组织化学研究显示，与WT相比，atprx 72突变体植物中的木质素单位含量低，木质素量减少。atprx 72突变体植物比WT植物生长更慢，具有更小的莲座丛和主茎，并且具有比WT植物更少的分枝和长角果。最后，叶绿素a荧光显示，在atprx 72突变体植物中，I破碎垂直条（PSII）和q（L）的显着降低，这可能与拟南芥代谢中碳分配和/或氧化还原当量利用的变化有关。结果表明AtPrx 72在木质素生物合成中起重要作用。此外，敲除植物能够响应和适应木质化不足。
Lignins result from the oxidative polymerization of three hydroxycinnamyl (p-coumaryl, coniferyl, and sinapyl) alcohols in a reaction mediated by peroxidases. The most important of these is the cationic peroxidase from Zinnia elegans (ZePrx), an enzyme considered to be responsible for the last step of lignification in this plant. Bibliographical evidence indicates that the arabidopsis peroxidase 72 (AtPrx72), which is homolog to ZePrx, could have an important role in lignification. For this reason, we performed a bioinformatic, histochemical, photosynthetic, and phenotypical and lignin composition analysis of an arabidopsis knock-out mutant of AtPrx72 with the aim of characterizing the effects that occurred due to the absence of expression of this peroxidase from the aspects of plant physiology such as vascular development, lignification, and photosynthesis. In silico analyses indicated a high homology between AtPrx72 and ZePrx, cell wall localization and probably optimal levels of translation of AtPrx72. The histochemical study revealed a low content in syringyl units and a decrease in the amount of lignin in the atprx72 mutant plants compared to WT. The atprx72 mutant plants grew more slowly than WT plants, with both smaller rosette and principal stem, and with fewer branches and siliques than the WT plants. Lastly, chlorophyll a fluorescence revealed a significant decrease in I broken vertical bar(PSII) and q (L) in atprx72 mutant plants that could be related to changes in carbon partitioning and/or utilization of redox equivalents in arabidopsis metabolism. The results suggest an important role of AtPrx72 in lignin biosynthesis. In addition, knock-out plants were able to respond and adapt to an insufficiency of lignification.