Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2009 Nov;230(6):1185-96.
doi: 10.1007/s00425-009-1016-1. Epub 2009 Sep 17.

Brassinosteroids promote photosynthesis and growth by enhancing activation of Rubisco and expression of photosynthetic genes in Cucumis sativus

Xiao-Jian Xia  1 , Li-Feng Huang, Yan-Hong Zhou, Wei-Hua Mao, Kai Shi, Jian-Xiang Wu, Tadao Asami, Zhixiang Chen, Jing-Quan Yu
Affiliations

Brassinosteroids promote photosynthesis and growth by enhancing activation of Rubisco and expression of photosynthetic genes in Cucumis sativus

Xiao-Jian Xia et al. Planta. 2009 Nov.

Abstract

Brassinosteroids (BRs) are a new group of plant growth substances that promote plant growth and productivity. We showed in this study that improved growth of cucumber (Cucumis sativus) plants after treatment with 24-epibrassinolide (EBR), an active BR, was associated with increased CO(2) assimilation and quantum yield of PSII (Phi(PSII)). Treatment of brassinazole (Brz), a specific inhibitor for BR biosynthesis, reduced plant growth and at the same time decreased CO(2) assimilation and Phi(PSII). Thus, the growth-promoting activity of BRs can be, at least partly, attributed to enhanced plant photosynthesis. To understand how BRs enhance photosynthesis, we have analyzed the effects of EBR and Brz on a number of photosynthetic parameters and their affecting factors, including the contents and activity of ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco). Northern and Western blotting demonstrated that EBR upregulated, while Brz downregulated, the expressions of rbcL, rbcS and other photosynthetic genes. In addition, EBR had a positive effect on the activation of Rubisco based on increased maximum Rubisco carboxylation rates (V (c,max)), total Rubisco activity and, to a greater extent, initial Rubisco activity. The accumulation patterns of Rubisco activase (RCA) based on immunogold-labeling experiments suggested a role of RCA in BR-regulated activation state of Rubisco. Enhanced expression of genes encoding other Calvin cycle genes after EBR treatment may also play a positive role in RuBP regeneration (J (max)), thereby increasing maximum carboxylation rate of Rubisco (V (c,max)). Thus, BRs promote photosynthesis and growth by positively regulating synthesis and activation of a variety of photosynthetic enzymes including Rubisco in cucumber.

PubMed Disclaimer

Similar articles

See all similar articles

Cited by

See all "Cited by" articles

References

    1. Curr Opin Plant Biol. 2002 Oct;5(5):388-95 - PubMed
    1. Plant Physiol. 1987 Sep;85(1):152-4 - PubMed
    1. Anal Biochem. 1976 May 7;72:248-54 - PubMed
    1. Plant Cell. 2002;14 Suppl:S97-110 - PubMed
    1. Planta. 1996 Apr;198(4):604-613 - PubMed

Publication types

MeSH terms

LinkOut - more resources