Journal
PLANT CELL REPORTS
Volume 28, Issue 10, Pages 1475-1486Publisher
SPRINGER
DOI: 10.1007/s00299-009-0747-6
Keywords
Isoprenoid biosynthesis; Oncidium Gower Ramsey; Promoter reporter fusion; Transgenic tobacco; Phylogenetic analysis; E. coli hdr complementation
Categories
Funding
- National Science Council, Taiwan [NSC 93-2313-B020-013]
Ask authors/readers for more resources
Two pathways are used by higher plants for the biosynthesis of isoprenoid precursors: the mevalonate pathway in the cytosol and a 2-C-methyl-d-erythritol 4-phosphate (MEP) pathway in the plastids, with 1-hydroxy-2-methyl-2-(E)-butenyl 4-diphosphate reductase (HDR) catalyzing the last step in the MEP pathway. In order to understand the contribution of MEP pathway in isoprenoid biosynthesis of Oncidium orchid, a full-length cDNA corresponding to HDR from the flower tissues of Oncidium Gower Ramsey was cloned. The deduced OncHDR amino acid sequence contains a plastid signal peptide at the N-terminus and four conserved cysteine residues. RT-PCR analysis of HDR in Oncidium flowering plants revealed ubiquitous expression in organs and tissues, with preferential expression in the floral organs. Phylogenetic analysis revealed evolutionary conservation of the encoding HDR protein sequence. The genomic sequence of the HDR in Oncidium is similar to that in Arabidopsis, grape, and rice in structure. Successful complementation by OncHDR of an E. coli hdr (-) mutant confirmed its function. Transgenic tobacco carrying the OncHDR promoter-GUS gene fusion showed expression in most tissues, as well as in reproductive organs, as revealed by histochemical staining. Light induced strong GUS expression driven by the OncHDR promoter in transgenic tobacco seedlings. Taken together, our data suggest a role for OncHDR as a light-activated gene.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available