Access

You are not currently logged in.

Access your personal account or get JSTOR access through your library or other institution:

login

Log in to your personal account or through your institution.

Control of sulphate assimilation and glutathione synthesis: interaction with N and C metabolism

Stanislav Kopriva and Heinz Rennenberg
Journal of Experimental Botany
Vol. 55, No. 404, Special Issue: Sulphur Metabolism in Plants— Integrating Complexity (August 2004), pp. 1831-1842
Published by: Oxford University Press
Stable URL: http://www.jstor.org/stable/24030618
Page Count: 12
  • Download ($42.00)
  • Cite this Item
Control of sulphate assimilation and glutathione synthesis: interaction with N and C metabolism
Preview not available

Abstract

Sulphate assimilation is an essential pathway being a source of reduced sulphur for various cellular processes and for the synthesis of glutathione, a major factor in plant stress defence. Many reports have shown that sulphate assimilation is well co-ordinated with the assimilation of nitrate and carbon. It has long been known that, during nitrate deficiency, sulphate assimilation is reduced and that the capacity to reduce nitrate is diminished in plants starved for sulphate. Only recently, however, was it shown that adenosine 5′ phosphosulphate reductase (APR), the key enzyme of sulphate assimilation, is regulated by carbohydrates. In plants treated with sucrose or glucose APR was induced, whereas the activity was strongly reduced in plants grown in CO2-free air. The availability of cysteine is a crucial factor in glutathione synthesis, but an adequate supply of glutamate and glycine are also important. The molecular mechanisms for the coordination of S, N, and C assimilation are not known. O-acetylserine, a precursor of cysteine, was proposed to be the signal regulating sulphate assimilation, but most probably is not the outgoing signal to N and C metabolism. cDNA arrays revealed the induction of genes involved in auxin synthesis upon S-starvation, pointing to a possible role of phytohormones. Clearly, despite significant progress in understanding the regulation of sulphate assimilation and glutathione synthesis, their co-ordination with N and C metabolism achieved, and several potential signal molecules identified, present knowledge is still far from being sufficient.

Page Thumbnails

  • Thumbnail: Page 
[1831]
    [1831]
  • Thumbnail: Page 
1832
    1832
  • Thumbnail: Page 
1833
    1833
  • Thumbnail: Page 
1834
    1834
  • Thumbnail: Page 
1835
    1835
  • Thumbnail: Page 
1836
    1836
  • Thumbnail: Page 
1837
    1837
  • Thumbnail: Page 
1838
    1838
  • Thumbnail: Page 
1839
    1839
  • Thumbnail: Page 
1840
    1840
  • Thumbnail: Page 
1841
    1841
  • Thumbnail: Page 
1842
    1842