title: Antisense-overexpression of the MsCOMT gene induces changes in lignin and total phenol contents in transgenic tobacco plants.
abstract: 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.
authors.affiliation: Bioherb Research Institute, Kangwon National University, Chuncheon, 200-701, South Korea. eunsooses@hanmail.net
authors.forename: Eun Soo
authors.initials: ES
authors.lastname: Seong
authors.forename: Ji Hye
authors.initials: JH
authors.lastname: Yoo
authors.forename: Jae Geun
authors.initials: JG
authors.lastname: Lee
authors.forename: Hee Young
authors.initials: HY
authors.lastname: Kim
authors.forename: In Seong
authors.initials: IS
authors.lastname: Hwang
authors.forename: Kweon
authors.initials: K
authors.lastname: Heo
authors.forename: Jae Kwang
authors.initials: JK
authors.lastname: Kim
authors.forename: Jung Dae
authors.initials: JD
authors.lastname: Lim
authors.forename: Erik J
authors.initials: EJ
authors.lastname: Sacks
authors.forename: Chang Yeon
authors.initials: CY
authors.lastname: Yu
mesh_terms: D000975:Antioxidants / Q000378:metabolism; D005419:Flavonoids / Q000378:metabolism; D015870:Gene Expression; D018506:Gene Expression Regulation, Plant; D005818:Genetic Engineering; D008031:Lignin / Q000378:metabolism*; D053858:Metabolic Networks and Pathways; D008780:Methyltransferases / Q000096:biosynthesis / Q000235:genetics*; D016254:Mutagenesis, Insertional; D019800:Phenol / Q000378:metabolism*; D018515:Plant Leaves / Q000235:genetics / Q000378:metabolism / Q000648:ultrastructure; D010940:Plant Proteins / Q000096:biosynthesis / Q000235:genetics*; D030821:Plants, Genetically Modified / Q000235:genetics / Q000378:metabolism / Q000648:ultrastructure; D006109:Poaceae / Q000201:enzymology / Q000235:genetics; D014026:Nicotiana / Q000235:genetics* / Q000378:metabolism / Q000648:ultrastructure; D059467:Transcriptome
chemical_list: D000975:Antioxidants; D005419:Flavonoids; D010940:Plant Proteins; D019800:Phenol; D008031:Lignin; D008780:Methyltransferases; C019608:caffeate O-methyltransferase