Bioherb Research Institute, Kangwon National University, Chuncheon, 200-701, South Korea.
Mol Biol Rep. 2013 Feb;40(2):1979-86. doi: 10.1007/s11033-012-2255-y. Epub 2012 Nov 16.
Initially, we isolated the caffeic acid O-methyltransferase (COMT) gene from Miscanthus sinensis (accession number HM062766.1). Next, we produced transgenic tobacco plants with down-regulated COMT gene expression to study its control of total phenol and lignin content and to perform morphological analysis. These transgenic plants were found to have reduced PAL and ascorbate peroxidases expression, which are related to the phenylpropanoid pathway and antioxidant activity. The MsCOMT-down-regulated plants had decreased total lignin in the leaves and stem compared with control plants. Reduced flavonol concentrations were confirmed in MsCOMT-down-regulated transgenic plants. We also observed a morphological difference, with reduced plant cell number in transgenic plants harboring antisense MsCOMT. The transgenic tobacco plants with down-regulated COMT gene expression demonstrate that COMT plays a crucial role related to controlling lignin and phenol content in plants. Also, COMT activity may be related to flavonoid production in the plant lignin pathway.
我们最初从芒（Miscanthus sinensis）中分离出咖啡酸-O-甲基转移酶（COMT）基因（登录号 HM062766.1）。然后，我们通过下调 COMT 基因表达生产了转基因烟草植物，以研究其对总酚和木质素含量的控制，并进行形态分析。这些转基因植物表现出 PAL 和抗坏血酸过氧化物酶表达降低，这与苯丙烷途径和抗氧化活性有关。与对照植物相比，MsCOMT 下调植物的叶片和茎中的总木质素减少。在 MsCOMT 下调的转基因植物中证实了类黄酮醇浓度降低。我们还观察到一个形态差异，携带反义 MsCOMT 的转基因植物的植物细胞数量减少。下调 COMT 基因表达的转基因烟草植物表明，COMT 在控制植物木质素和酚含量方面起着关键作用。此外，COMT 活性可能与植物木质素途径中类黄酮的产生有关。
