Library Open Repository

Grapes on Steroids. Brassinosteroids Are Involved in Grape Berry Ripening

Downloads

Downloads per month over past year

Symons, GM and Davies, C and Shavrukov, Y and Dry, IB and Reid, JB and Thomas, MR (2006) Grapes on Steroids. Brassinosteroids Are Involved in Grape Berry Ripening. Plant Physiology, 140. pp. 150-158. ISSN 0032-0889

[img] PDF
Symons_et_al_2006_(grapes_on_steroids).pdf | Request a copy
Full text restricted
Available under University of Tasmania Standard License.

Abstract

Fruit ripening is a unique plant developmental process with direct implications for our food supply, nutrition, and health. In contrast to climacteric fruit, where ethylene is pivotal, the hormonal control of ripening in nonclimacteric fruit, such as grape (Vitis vinifera), is poorly understood. Brassinosteroids (BRs) are steroidal hormones, essential for normal plant growth and development but not previously implicated in the ripening of nonclimacteric fruit. Here we show that increases in endogenous BR levels, but not indole-3-acetic acid (IAA) or GA levels, are associated with ripening in grapes. Putative grape homologs of genes encoding BR biosynthesis enzymes (BRASSINOSTEROID-6-OXIDASE and DWARF1) and the BR receptor (BRASSINOSTEROID INSENSITIVE 1) were isolated, and the function of the grape BRASSINOSTEROID-6-OXIDASE gene was confirmed by transgenic complementation of the tomato (Lycopersicon esculentum) extreme dwarf (dx/dx) mutant. Expression analysis of these genes during berry development revealed transcript accumulation patterns that were consistent with a dramatic increase in endogenous BR levels observed at the onset of fruit ripening. Furthermore, we show that application of BRs to grape berries significantly promoted ripening, while brassinazole, an inhibitor of BR biosynthesis, significantly delayed fruit ripening. These results provide evidence that changes in endogenous BR levels influence this key developmental process. This may provide a significant insight into the mechanism controlling ripening in grapes, which has direct implications for the logistics of grape production and down-stream processing.

Item Type: Article
Journal or Publication Title: Plant Physiology
Page Range: pp. 150-158
ISSN: 0032-0889
Identification Number - DOI: 10.1104/pp.105.070706
Additional Information: Copyright © 2006 by the American Society of Plant Biologists
Date Deposited: 19 Aug 2011 00:19
Last Modified: 18 Nov 2014 04:21
URI: http://eprints.utas.edu.au/id/eprint/11572
Item Statistics: View statistics for this item

Repository Staff Only (login required)

Item Control Page Item Control Page