title: Evaluation of a novel promoter from Populus trichocarpa for mature xylem tissue specific gene delivery.
abstract: Wood (i.e., secondary xylem) is an important raw material for many industrial applications. Mature xylem (MX) tissue-specific genetic modification offers an effective means to improve the chemical and physical properties of the wood. Here, we describe a promoter that drives strong gene expression in a MX tissue-specific manner. Using whole-transcriptome genechip analyses of different tissue types of poplar, we identified five candidate genes that had strong expression in the MX tissue. The putative promoter sequences of the five MX-specific genes were evaluated for their promoter activity in both transgenic Arabidopsis and poplar. Among them, we found the promoter of Potri.013G007900.1 (called the PtrMX3 promoter) had the strongest activity in MX and thus was further characterized. In the stem and root tissues of transgenic Arabidopsis plants, the PtrMX3 promoter activity was found exclusively in MX tissue. MX-specific activity of the promoter was reproduced in the stem tissue of transgenic poplar plants. The PtrMX3 promoter activity was not influenced by abiotic stresses or exogenously applied growth regulators, indicating the PtrMX3 promoter is bona fide MX tissue-specific. Our study provides a strong MX-specific promoter for MX-specific modifications of woody biomass.
authors.affiliation: Department of Plant & Environmental New Resources, Kyung Hee University, Yongin 17104, Republic of Korea.
authors.forename: Van Phap
authors.initials: VP
authors.lastname: Nguyen
authors.affiliation: Department of Plant & Environmental New Resources, Kyung Hee University, Yongin 17104, Republic of Korea; Division of Forest Biotechnology, Korea Forest Research Institute, Suwon 16631, Republic of Korea.
authors.forename: Jin-Seong
authors.initials: JS
authors.lastname: Cho
authors.affiliation: Division of Forest Biotechnology, Korea Forest Research Institute, Suwon 16631, Republic of Korea.
authors.forename: Young-Im
authors.initials: YI
authors.lastname: Choi
authors.affiliation: Department of Genetic Engineering & Crop Biotech Institute, Kyung Hee University, Yongin 17104, Republic of Korea.
authors.forename: Sang-Won
authors.initials: SW
authors.lastname: Lee
authors.affiliation: Department of Horticulture and Department of Forestry, Michigan State University, East Lansing, MI 48824-1222, USA.
authors.forename: Kyung-Hwan
authors.initials: KH
authors.lastname: Han
authors.affiliation: Department of Plant & Environmental New Resources, Kyung Hee University, Yongin 17104, Republic of Korea. Electronic address: jhko@khu.ac.kr.
authors.forename: Jae-Heung
authors.initials: JH
authors.lastname: Ko
mesh_terms: D017360:Arabidopsis / Q000187:drug effects / Q000235:genetics; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D018014:Gene Transfer Techniques; D005966:Glucuronidase / Q000378:metabolism; D009928:Organ Specificity / Q000187:drug effects / Q000235:genetics; D010937:Plant Growth Regulators / Q000494:pharmacology; D030821:Plants, Genetically Modified; D032107:Populus / Q000187:drug effects / Q000235:genetics*; D011401:Promoter Regions, Genetic; D052584:Xylem / Q000187:drug effects / Q000235:genetics*
chemical_list: D010937:Plant Growth Regulators; D005966:Glucuronidase
keywords: Biotechnology; Mature xylem; Poplar; Tissue-specific promoter; Woody biomass