Autor: Valerie Frankard, Marc Vauterin, Michel Jacobs
Rok vydání: 1999
Předmět:
Zdroj: Plant Molecular Biology. 39:695-708
ISSN: 0167-4412
DOI: 10.1023/a:1006132428623
Popis: Lysine synthesis in prokaryotes, some phycomycetes and higher plants starts with the condensation of L-aspartate-β-semialdehyde (L-ASA) and pyruvate into dihydrodipicolinic acid. The enzyme that catalyses this step, dihydrodipicolinate synthase (DHDPS), is inhibited by the end-product lysine and is therefore thought to have a regulatory control on lysine synthesis. We have cloned and sequenced an Arabidopsis thaliana DNA fragment containing 900 bases upstream of the dhdps coding sequence. A transcriptional fusion of this fragment with the β-glucuronidase reporter gene (uidA, Gus) was used to study the transcription properties of this promoter fragment (DS). No lysine-induced repression on transcription could be detected. Expression of DS-Gus activity in transformed Arabidopsis thaliana and Nicotiana tabacum was found to be cell type-specific. In the vegetative parts of the plant, GUS activity was located in meristems and young vasculature of roots, in vasculature of stem and leaves and in the meristems of young shoots. In flowers, high expression was found in the carpels, style, stigma, developing embryos, tapetum of young anthers and pollen. We demonstrated that the Arabidopsis DS promoter can direct its cell type-specific expression in a heterologous plant, Nicotiana tabacum. The importance of transcriptional regulation of the dhdps gene, and in more general genes involved in amino acid biosynthesis, is discussed.
Databáze: OpenAIRE
Externí odkaz: