Article
Regulation of Sulfur-Responsive Gene Expression by Exogenously Applied Cytokinins in Arabidopsis thaliana

Authors: Ohkama N.1; Takei K.2; Sakakibara H.2; Hayashi H.1; Yoneyama T.1; Fujiwara T.1

Source: Plant and Cell Physiology, Volume 43, Number 12, 15 December 2002 , pp. 1493-1501(9)

Publisher: Oxford University Press

Key:
Free Content - Free Content
New Content - New Content
Subscribed Content - Subscribed Content
Free Trial Content - Free Trial Content

Abstract:

Effects of plant hormones on a sulfur-deficiency responsive element (bgrSR) from the promoter region of the bgr subunit gene of bgr-conglycinin, a major seed storage protein of soybean, were investigated using transgenic Arabidopsis thaliana. Among the hormones tested, the cytokinins, trans-zeatin (Z) and trans-zeatin riboside, upregulated gene expression directed by the bgrSR element both in the presence and in the absence of sulfate in the medium. Z also increased transcript accumulation of two endogenous sulfur-responsive genes, the adenosine 5prime-phosphosulfate reductase (APR1) and the Sultr2;2, a sulfate transporter. Concentrations of cytokinins were unaltered during early stages of sulfur starvation when expression of these genes was upregulated. Z did not alter concentrations of O-acetyl-L-serine, a positive regulator of gene expression in sulfur starvation response. Concentrations of sucrose, which is known to upregulate expression of APR1, were increased in rosette leaves by Z. Sucrose application to the medium also increased expression directed by the bgrSR element, although sucrose concentrations in tissues were not significantly altered by sulfur availability. These results suggest that exogenously applied cytokinins positively regulate expression of these sulfur responsive genes through a pathway independent of that from sulfur starvation, possibly through increasing sucrose concentrations in tissues.

Document Type: Original article

Affiliations: 1: Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, 113-8657 Japan 2: RIKEN (The Institute of Physical and Chemical Research) Plant Science Center, Suehiro, Tsurumi-ku, Yokohama, Kanagawa, 230-0045 Japan

The full text electronic article is available for purchase. You will be able to download the full text electronic article after payment.

$40.03 plus tax      Refund Policy

 

OR

Back to top

Key:
Free Content - Free Content
New Content - New Content
Subscribed Content - Subscribed Content
Free Trial Content - Free Trial Content
Share this item with others: These icons link to social bookmarking sites where readers can share and discover new web pages.
Page Help Click here for Page Help
Shopping cart
Tools
Sign in






Need to register?
Sign up here
Text size: A | A | A | A