Identification of UV-B light-responsive regions in the promoter of the tryptophan decarboxylase gene from Catharanthus roseus

Identification of UV-B light-responsive regions in the promoter of the tryptophan decarboxylase... The tryptophan decarboxylase (Tdc) gene encodes a key enzyme in the biosynthesis of terpenoid indole alkaloids (TIAs) in Catharanthus roseus. TIAs absorb ultraviolet light (UV) and putative functions in plants include a role as UV protectants. In support of this possible function we demonstrate here that UV light induces accumulation of several TIAs as well as expression of the Tdc gene in C. roseus. In addition, in tobacco a Tdc-gusA construct was found to be specifically induced by UV-B light. Lack of induction by UV-A or other wavelengths of light indicate that Tdc expression is regulated by a specific UV-B receptor and corresponding signal transduction pathway. To identify UV-responsive Tdc promoter elements, a loss-of-function analysis was performed, in which deletion derivatives were fused to the gusA reporter gene and analysed in transgenic tobacco plants. Truncation of the Tdc promoter from −1818 (relative to the start of transcription) to −160 reduced expression levels two-fold without affecting the qualitative UV response. Deletion to −37 further reduced expression levels five-fold, but the Δ37 promoter also remained UV-responsive. Subsequently, the −160 to −37 region was further studied by gain-of-function experiments, in which the transcriptional activities of tetramerized subfragments fused to truncated promoters were analysed. Combination of the data identified several functional regions in the −160 to +198 promoter. The −160 to −99 region acts as the main transcriptional enhancer. UV-responsive elements appeared to be redundant in the −160 Tdc promoter and to reside between −99 and −37 and between −37 and +198. http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png Plant Molecular Biology Springer Journals

Identification of UV-B light-responsive regions in the promoter of the tryptophan decarboxylase gene from Catharanthus roseus

Loading next page...
 
/lp/springer_journal/identification-of-uv-b-light-responsive-regions-in-the-promoter-of-the-qT82ufFQ6i
Publisher
Kluwer Academic Publishers
Copyright
Copyright © 1999 by Kluwer Academic Publishers
Subject
Life Sciences; Biochemistry, general; Plant Sciences; Plant Pathology
ISSN
0167-4412
eISSN
1573-5028
D.O.I.
10.1023/A:1006321100550
Publisher site
See Article on Publisher Site

Abstract

The tryptophan decarboxylase (Tdc) gene encodes a key enzyme in the biosynthesis of terpenoid indole alkaloids (TIAs) in Catharanthus roseus. TIAs absorb ultraviolet light (UV) and putative functions in plants include a role as UV protectants. In support of this possible function we demonstrate here that UV light induces accumulation of several TIAs as well as expression of the Tdc gene in C. roseus. In addition, in tobacco a Tdc-gusA construct was found to be specifically induced by UV-B light. Lack of induction by UV-A or other wavelengths of light indicate that Tdc expression is regulated by a specific UV-B receptor and corresponding signal transduction pathway. To identify UV-responsive Tdc promoter elements, a loss-of-function analysis was performed, in which deletion derivatives were fused to the gusA reporter gene and analysed in transgenic tobacco plants. Truncation of the Tdc promoter from −1818 (relative to the start of transcription) to −160 reduced expression levels two-fold without affecting the qualitative UV response. Deletion to −37 further reduced expression levels five-fold, but the Δ37 promoter also remained UV-responsive. Subsequently, the −160 to −37 region was further studied by gain-of-function experiments, in which the transcriptional activities of tetramerized subfragments fused to truncated promoters were analysed. Combination of the data identified several functional regions in the −160 to +198 promoter. The −160 to −99 region acts as the main transcriptional enhancer. UV-responsive elements appeared to be redundant in the −160 Tdc promoter and to reside between −99 and −37 and between −37 and +198.

Journal

Plant Molecular BiologySpringer Journals

Published: Oct 16, 2004

References

You’re reading a free preview. Subscribe to read the entire article.


DeepDyve is your
personal research library

It’s your single place to instantly
discover and read the research
that matters to you.

Enjoy affordable access to
over 18 million articles from more than
15,000 peer-reviewed journals.

All for just $49/month

Explore the DeepDyve Library

Search

Query the DeepDyve database, plus search all of PubMed and Google Scholar seamlessly

Organize

Save any article or search result from DeepDyve, PubMed, and Google Scholar... all in one place.

Access

Get unlimited, online access to over 18 million full-text articles from more than 15,000 scientific journals.

Your journals are on DeepDyve

Read from thousands of the leading scholarly journals from SpringerNature, Elsevier, Wiley-Blackwell, Oxford University Press and more.

All the latest content is available, no embargo periods.

See the journals in your area

DeepDyve

Freelancer

DeepDyve

Pro

Price

FREE

$49/month
$360/year

Save searches from
Google Scholar,
PubMed

Create lists to
organize your research

Export lists, citations

Read DeepDyve articles

Abstract access only

Unlimited access to over
18 million full-text articles

Print

20 pages / month

PDF Discount

20% off