Lignin synthesis mediated by CCoAOMT enzymes is required for the tolerance against excess Cu in Oryza sativa
Lignin synthesis mediated by CCoAOMT enzymes is required for the tolerance against excess Cu in Oryza sativa
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CCoAOMT 酶介导的木质素合成是水稻耐受过量铜所必需的
DOI：
10.1016/j.envexpbot.2020.104059
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发表时间：
2020-07
影响因子：
5.7
通讯作者：
Xia Yan
中科院分区：
文献类型：
--
作者：
Su Nana;Ling Fei;Xing Aiming;Zhao Haihao;Zhu Yongwei;Wang Ying;Deng Xiaopeng;Wang Chunfei;Xu Xiaoming;Hu Zhubing;Cui Jin;Shen Zhenguo;Xia Yan
木质素积累是对重金属毒性的一般反应；然而，其根本机制尚不清楚。我们分离出两个水稻木质素缺陷突变体（ldm1和ldm2）；两者均表现出机械强度和木质素积累降低。此外，两种突变体中木质素的紫丁香基和愈创木基单位的水平均降低。两种突变体都比野生型植物对过量的铜更敏感，这可能是由于突变体的叶鞘和根中的铜比野生型植物更多。此外，ldm1和ldm2突变体中铜在细胞壁中的保留发生了改变。基因型分析证实ldm1在OsCCoAMT1的最后一个外显子中有一个T-DNA插入，ldm2在OsCCoAMT20的第二个外显子中有一个T-DNA插入。一致的是，两种突变体在所有检查的组织中都表现出显着降低的 CCoAOMT 酶活性，其催化甲基从 S-腺苷-L蛋氨酸 (SAM) 转移到咖啡酰-CoA 或 5-羟基阿魏酰-CoA 的苯碳 3 位。此外，在过量铜胁迫下，叶鞘和根中OsCCoAOMT1和CCoAOMT20的表达以及CCoAOMT活性上调，表明OsCCoAOMT1和OsCCoAOMT20介导的木质素合成在适应过量铜胁迫中发挥重要作用。基于木质素在植物细胞壁中封存重金属的作用，我们推测增强木质素合成可能是减轻铜离子毒性的适应性策略。
Lignin accumulation is a general response to heavy metal toxicity; however, the underlying mechanism is unclear. We isolated two ricelignin-defectivemutants (ldm1andldm2); both showed reduced mechanical strength and lignin accumulation. Also, the levels of the syringyl and guaiacyl units of lignin were decreased in both mutants. Both mutants were more hypersensitive to excess Cu than wild-type plants, possibly resulting from more Cu in leaf sheaths and roots of the mutants than wild-type plants. Moreover, Cu retention in the cell wall was altered in theldm1andldm2mutants. Genotypic analysis confirmed thatldm1has a T-DNA insert in the last exon ofOsCCoAMT1andldm2in the second exon ofOsCCoAMT20. Consistently, both mutants displayed significantly decreased CCoAOMT enzymatic activity in all tissues examined, which catalyzed the transfer of methyl groups from S-adeosyl-Lmethionin (SAM) to benzene carbon 3 position of caffeoyl-CoA or 5-hydroxyferuloyl-CoA. Furthermore, the expression ofOsCCoAOMT1andCCoAOMT20and CCoAOMT activity were upregulated in leaf sheaths and roots under excess Cu, suggesting that lignin synthesis mediated by OsCCoAOMT1 and OsCCoAOMT20 plays an important role in the adaptation to excess Cu stress. Based on the role of lignin in the sequestration of heavy metals in the plant cell wall, we speculate that enhancement of lignin synthesis may be an adaptive strategy to alleviate the toxicity of Cu ions.
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影响因子：
4.3
作者：
Herrero, Joaquin;Fernandez-Perez, Francisco;Miguel Zapata, Jose
通讯作者：
Miguel Zapata, Jose
影响因子：
3.5
作者：
Gaoyang Zhang;Yujia Zhang;Jiantang Xu;Xiaoping Niu;J. Qi;A. Tao;Liwu Zhang;Pingping Fang;
通讯作者：
Gaoyang Zhang;Yujia Zhang;Jiantang Xu;Xiaoping Niu;J. Qi;A. Tao;Liwu Zhang;Pingping Fang;
影响因子：
3.8
作者：
G. Pinçon;S. Maury;Laurent Hoffmann;P. Geoffroy;C. Lapierre;B. Pollet;M. Legrand
通讯作者：
G. Pinçon;S. Maury;Laurent Hoffmann;P. Geoffroy;C. Lapierre;B. Pollet;M. Legrand
影响因子：
7.4
作者：
Cabané, M;Pireaux, JC;Lapierre, C
通讯作者：
Lapierre, C
影响因子：
2.9
作者：
Pomar, F;Merino, F;Barceló, AR
通讯作者：
Barceló, AR