Poster abstracts

Poster number 156 submitted by Andrew Weeks

Zinc-dependent regulation of sod1 mRNA transcript levels.

Andrew T. Weeks (Department of Human Nutrition,The Ohio State University), Derek M. Boehm (Department of Molecular Genetics, The Ohio State University), Amanda J. Bird (Department of Human Nutrition, Department of Molecular Genetics, The Ohio State University)

Abstract:
Zinc is an essential nutrient for all life. Within cells, zinc functions as a structural or catalytic cofactor for many enzymes including the highly conserved and abundant cytosolic Cu2+/Zn2+ binding enzyme superoxide dismutase-1 (Sod1). Here we show that in the model system Schizosaccharomyces pombe, sod1 mRNA levels are decreased in zinc-limiting conditions. We also find that this regulation is not dependent upon Loz1, the major regulator of zinc homeostasis, nor on other stress-related transcription factors known to regulate sod1 gene expression, suggesting a novel regulatory mechanism. We show that plasmids containing sod1 sequence inclusive of either a 500 bp or ~1.8 kb promoter though the 3’ UTR are sufficient to confer zinc-dependent regulation. Using reporter analysis, we demonstrate that the 1.8 kb sod1 promoter is insufficient to confer regulation by zinc. Further analyses reveal that the sod1 3’ UTR and the RNA-binding protein Zfs1 are both required for the regulation by zinc, although the 3’ UTR is insufficient for this regulation. Furthermore, zinc-dependent regulation is impaired in strains containing gene deletions of constituents of the Ccr4-Not complex.

Keywords: sod1 , mRNA regulation, zinc-dependent