Biology
Document Type
Article
Abstract
Regulation of antioxidant enzymes is critical to control the levels of reactive oxygen species in cell compartments highly susceptible to oxidative stress. In this work, we studied the regulation of a chloroplastic iron superoxide dismutase (Fe-SOD) from Lingulodinium polyedrum (formerly Gonyaulax polyedra) under different physiological conditions. A cDNA-encoding Fe-SOD was isolated from this dinoflagellate, showing high sequence similarity to cyanobacterial, algal, and plant Fe-SODs. Under standard growth conditions, on a 12:12-h light-dark cycle, Lingulodinium polyedrum Fe-SOD exhibited a daily rhythm of activity and cellular abundance with the maximum occurring during the middle of the light phase. Northern analyses showed that this rhythmicity is not related to changes in Fe-SOD mRNA levels, indicative of translational regulation. By contrast, conditions of metal-induced oxidative stress resulted in higher levels of Fe-SOD transcripts, suggesting that transcriptional control is responsible for increased protein and activity levels. Daily (circadian) and metal-induced up-regulation of Fe-SOD expression in L. polyedrum are thus mediated by different regulatory pathways, allowing biochemically distinct changes appropriate to oxidative challenges.
Publication Title
Journal of Biological Chemistry
Publication Date
6-8-2001
Volume
276
Issue
23
First Page
19989
Last Page
19993
ISSN
0021-9258
DOI
10.1074/jbc.M101169200
Repository Citation
Okamoto, O. Keith; Robertson, Deborah L.; Fagan, Thomas F.; Hastings, J. Woodland; and Colepicolo, Pio, "Different Regulatory Mechanisms Modulate the Expression of a Dinoflagellate Iron-Superoxide Dismutase" (2001). Biology. 44.
https://commons.clarku.edu/faculty_biology/44
Creative Commons License
This work is licensed under a Creative Commons Attribution 3.0 License.
Copyright Conditions
Okamoto, O. K., Robertson, D. L., Fagan, T. F., Hastings, J. W., & Colepicolo, P. (2001). Different regulatory mechanisms modulate the expression of a dinoflagellate iron-superoxide dismutase. Journal of Biological Chemistry, 276(23), 19989-19993.
