title: LuFLA1PRO and LuBGAL1PRO promote gene expression in the phloem fibres of flax (Linum usitatissimum).
abstract: Cell type-specific promoters were identified that drive gene expression in an industrially important product. To identify flax (Linum usitatissimum) gene promoters, we analyzed the genomic regions upstream of a fasciclin-like arabinogalactan protein (LuFLA1) and a beta-galactosidase (LuBGAL1). Both of these genes encode transcripts that have been found to be highly enriched in tissues bearing phloem fibres. Using a beta-glucuronidase (GUS) reporter construct, we found that a 908-bp genomic sequence upstream of LuFLA1 (LuFLA1PRO) directed GUS expression with high specificity to phloem fibres undergoing secondary cell wall development. The DNA sequence upstream of LuBGAL1 (LuBGAL1PRO) likewise produced GUS staining in phloem fibres with developing secondary walls, as well as in tissues of developing flowers and seed bolls. These data provide further evidence of a specific role for LuFLA1 in phloem fibre development, and demonstrate the utility of LuFLA1PRO and LuBGAL1PRO as tools for biotechnology and further investigations of phloem fibre development.
authors: Department of Biological Sciences, University of Alberta, Edmonton, AB, T6G 2E9, Canada. nhobson@ualberta.ca
authors: Neil
authors: N
authors: Hobson
authors: Michael K
authors: MK
authors: Deyholos
mesh_terms: D002473:Cell Wall / Q000502:physiology; D019295:Computational Biology; D018744:DNA, Plant / Q000235:genetics; D019597:Flax / Q000235:genetics* / Q000378:metabolism; D018506:Gene Expression Regulation, Plant; D017930:Genes, Reporter; D009088:Mucoproteins / Q000235:genetics / Q000378:metabolism*; D052585:Phloem / Q000235:genetics* / Q000378:metabolism; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D030821:Plants, Genetically Modified / Q000235:genetics / Q000378:metabolism; D011401:Promoter Regions, Genetic; D017422:Sequence Analysis, DNA
chemical_list: D018744:DNA, Plant; D009088:Mucoproteins; D010940:Plant Proteins; C006619:arabinogalactan proteins