Copper deficiency induced expression of Fe-superoxide dismutase gene in Matteuccia struthiopteris.

Iron-superoxide dismutase (Fe-SOD) activity was not detected in extracts from the leaves of ferns, Equisetum arvense and Matteuccia struthiopteris. To know why ferns lack Fe-SOD activity, the Fe-SOD like gene (MsFeSOD1) was isolated from M. struthiopteris and its expression was investigated with a focus on the metals Fe and Cu using the prothalli of the fern. The expression of MsFeSOD1 mRNA was induced by a deficiency of Cu, but Fe-SOD activity was not detected. The recombinant protein of MsFeSOD1 produced in E. coli showed Fe-SOD activity. These findings suggest that the fern Fe-SOD like gene was transcriptionally regulated by Cu but an additional mechanism is involved in the formation of an active enzyme.