Light regulation of assimilatory sulphate reduction in Arabidopsis thaliana
Kopriva S, Muheim R, Koprivova A, Trachsel N, Catalano C, Suter M, Brunold C (1999)
Publication Type: Journal article
Publication year: 1999
Journal
Book Volume: 20
Pages Range: 37-44
Journal Issue: 1
DOI: 10.1046/j.1365-313X.1999.00573.x
Abstract
Adenosine 5'-phosphosulphate reductase (APR) is considered to be a key enzyme of sulphate assimilation in higher plants. We analysed the diurnal fluctuations of total APR activity and protein accumulation together with the mRNA levels of three APR isoforms of Arabidopsis thaliana. The APR activity reached maximum values 4h after light onset in both shoots and roots; the minimum activity was detected at the beginning of the night. During prolonged light, the activity remained stable and low in shoots, but followed the normal rhythm in roots. On the other hand, the activity decreased rapidly to undetectable levels within 24h of prolonged darkness both in shoots and roots. Subsequent re-illumination restored the activity to 50% in shoots and to 20% in roots within 8h. The mRNA levels of all three APR isoforms showed a diurnal rhythm, with a maximum at 2h after light onset. The variation of APR2 mRNA was more prominent compared to APR1 and APR3. 35SO4/2- feeding experiments showed that the incorporation of 35S into reduced sulphur compounds in vivo was significantly higher in light than in the dark. A strong increase of mRNA and protein accumulation as well as enzyme activity during the last 4h of the dark period was observed, implying that light was not the only factor involved in APR regulation. Indeed, addition of 0.5% sucrose to the nutrient solution after 38 h of darkness led to a sevenfold increase of root APR activity over 6h. We therefore conclude that changes in sugar concentrations are also involved in APR regulation.
Authors with CRIS profile
Involved external institutions
Universität Bern
Switzerland (CH)
Università degli Studi di Palermo
Italy (IT)
Eidgenössische Forschungsanstalt für Agraroekologie und Landbau
Switzerland (CH)
Switzerland (CH)
Università degli Studi di Palermo
Italy (IT)
Eidgenössische Forschungsanstalt für Agraroekologie und Landbau
Switzerland (CH)
How to cite
APA:
Kopriva, S., Muheim, R., Koprivova, A., Trachsel, N., Catalano, C., Suter, M., & Brunold, C. (1999). Light regulation of assimilatory sulphate reduction in Arabidopsis thaliana. Plant Journal, 20(1), 37-44. https://doi.org/10.1046/j.1365-313X.1999.00573.x
MLA:
Kopriva, Stanislav, et al. "Light regulation of assimilatory sulphate reduction in Arabidopsis thaliana." Plant Journal 20.1 (1999): 37-44.
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