title: Identification of the CAD gene from Eucalyptus urophylla GLU4 and its functional analysis in transgenic tobacco.
abstract: Cinnamyl alcohol dehydrogenase (CAD) catalyzes the final step in lignin biosynthesis. The genus Eucalyptus belongs to the family Myrtaceae, which is the main cultivated species in China. Eucalyptus urophylla GLU4 (GLU4) is widely grown in Guangxi. It is preferred for pulping because of its excellent cellulose content and fiber length. Based on GLU4 and CAD gene expression, a Eucalyptus variety low in lignin content should be obtained using transgenic technology, which could reduce the cost of pulp and improve the pulping rate, and have favorable prospects for application. However, the role and function of CAD in GLU4 is still unclear. In the present study, EuCAD was cloned from GLU4 and identified using bioinformatic tools. Subsequently, in order to evaluate its impact on lignin synthesis, a full-length EuCAD RNAi vector was constructed, and transgenic tobacco was obtained via Agrobacterium-mediated transformation. A significant decrease in CAD expression and lignin content in transgenic tobacco demonstrated a key role for EuCAD in lignin biosynthesis and established a regulatory role for RNAi. In our study, the direct molecular basis of EuCAD expression was determined, and the potential regulatory effects of this RNAi vector on lignin biosynthesis in E. urophylla GLU4 were demonstrated. Our results provide a theoretical basis for the study of lignin biosynthesis in Eucalyptus.
authors.affiliation: School of Biology Science and Biotechnology, Beijing Forestry University, Beijing, China gfri_bwchen@163.com.|Guangxi Key Laboratory of Superior Timber Trees Resource Cultivation, Guangxi Forestry Research Institute, Nanning, China gfri_bwchen@163.com.
authors.forename: B W
authors.initials: BW
authors.lastname: Chen
authors.affiliation: Guangxi Key Laboratory of Superior Timber Trees Resource Cultivation, Guangxi Forestry Research Institute, Nanning, China.
authors.forename: Y F
authors.initials: YF
authors.lastname: Xiao
authors.affiliation: Guangxi Key Laboratory of Superior Timber Trees Resource Cultivation, Guangxi Forestry Research Institute, Nanning, China.
authors.forename: J J
authors.initials: JJ
authors.lastname: Li
authors.affiliation: Guangxi Key Laboratory of Superior Timber Trees Resource Cultivation, Guangxi Forestry Research Institute, Nanning, China.
authors.forename: H L
authors.initials: HL
authors.lastname: Liu
authors.affiliation: Guangxi Key Laboratory of Superior Timber Trees Resource Cultivation, Guangxi Forestry Research Institute, Nanning, China.
authors.forename: Z H
authors.initials: ZH
authors.lastname: Qin
authors.affiliation: School of Biology Science and Biotechnology, Beijing Forestry University, Beijing, China.
authors.forename: Y
authors.initials: Y
authors.lastname: Gai
authors.affiliation: School of Biology Science and Biotechnology, Beijing Forestry University, Beijing, China gfri_bwchen@163.com.
authors.forename: X N
authors.initials: XN
authors.lastname: Jiang
mesh_terms: D000429:Alcohol Oxidoreductases / Q000235:genetics* / Q000378:metabolism; D002681:China; D003001:Cloning, Molecular / Q000379:methods*; D005052:Eucalyptus / Q000201:enzymology* / Q000235:genetics; D018506:Gene Expression Regulation, Plant; D008031:Lignin / Q000096:biosynthesis; D010802:Phylogeny; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D030821:Plants, Genetically Modified / Q000254:growth & development; D014026:Nicotiana / Q000235:genetics* / Q000254:growth & development
chemical_list: D010940:Plant Proteins; D008031:Lignin; D000429:Alcohol Oxidoreductases; C018656:cinnamyl alcohol dehydrogenase