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David J. Eide
Professor of Nutritional Sciences
B.S. 1981, University of Minnesota
Ph.D. 1987, University of Wisconsin
Emphasis Group(s):
Biochemical and Molecular Nutrition
Research Interests:
Nutritional genomics and molecular responses to changes in nutrient status.
Research Summary:
In our research, we ask a basic question in biology, i.e.
how do cells respond to an ever-changing environment
of nutrient availability? This
is a fundamental issue for all organisms including free-living
and pathogenic microbes, as well as multicellular organisms
such as plants and mammals.Our studies are focused on zinc,
an essential metal nutrient, and the yeast Saccharomyces
cerevisiae. This simple eukaryote has proven to be a great
model for the study
of many important cellular processes including the responses
of cells to conditions of nutrient stress. The success of
yeast as an experimental
model stems from our ability to manipulate this organism
using genetics and molecular biology.
In S. cerevisiae, the
Zap1 transcription factor is the key player in the response to zinc
deficiency. This metal-responsive regulatory protein controls the
expression of many genes in yeast. For most of its target genes, Zap1
acts as a transcriptional activator and increases expression when
zinc levels are low. In a few other cases, Zap1 acts as a transcriptional
repressor. Using transcriptome profiling with DNA microarrays and
other approaches, we have discovered that Zap1 regulates many genes
in the yeast genome. These studies indicate that more than 80 genes
in yeast are direct targets of Zap1 activation. In addition, over
30 genes are repressed in a Zap1-dependent manner indicating that
additional modes of regulation exist.
This collection of Zap1-regulated genes is providing exciting
new insights into how cells respond to nutrient stress. These strategies
of
stress response include up-regulation of plasma membrane
zinc uptake transporters
and transporters responsible for mobilizing intracellular
stores of zinc. In addition, transporters responsible for
moving zinc into organelles
such as the endoplasmic reticulum are also induced. Collectively,
we refer to these as “homeostatic” responses because they
serve to maintain zinc levels within the cell. We have
also discovered a number
of other responses that play an “adaptive” role. These
adaptive responses aid cell growth under conditions of zinc deficiency
and
include remodeling
of phospholipid synthesis, oxidative stress tolerance,
and sulfate assimilation. All together, we have characterized the role
of about
25 of the more than 100 Zap1 target genes. Much of our
future
work will be directed toward understanding the role of
the other ~80 Zap1 targets. The analysis of these genes will provide
great insight
into how cells of all organisms deal with the stress of
nutrient deficiency.
Representative Publications:
Eide, D.J. Homeostatic and adaptive responses to zinc deficiency in Saccharomyces
cerevisiae. J. Biol. Chem. 284: 18565-18569 (2009)
Qiao, W., Ellis, C., Steffen, J., Wu, C., and Eide, D. Zinc status and vacuolar
zinc transporters control alkaline phosphatase accumulation
and activity in Saccharomyces cerevisiae. Mol. Microbiol.
72:320-34 (2009).
Wu, C., Bird, A., Chung, L., Newton, M., Winge, D., and Eide, D. Differential
control of Zap1-regulated genes in response to zinc deficiency
in Saccharomyces cerevisiae. BMC Genomics, 9:370 (2008).
Wu, C., Bird, A., Winge, D. and Eide,
D. Regulation of the yeast Tsa1 peroxiredoxin by Zap1 is
an adaptive response to the oxidative stress of zinc deficiency.
J. Biol. Chem. 282:2184-2195 (2007).
Mao, X., Kim, B., Wang, F., Eide,
D., and Petris, M. A histidine-rich cluster mediates the
ubiquitination and degradation of the human zinc transporter,
hZIP4, and protects against zinc cytotoxicity. J. Biol. Chem.
282:6992-7000 (2007).
Simm, C., Lahner, B., Salt, D., LeFurgey,
A., Ingram, P., Yandell, B., and Eide, D. The yeast vacuole
in zinc storage and intracellular zinc distribution. Eukaryotic
Cell, 6:1166-77 (2007).
Bird, A., Gordon, M., Eide, D., and
Winge, D. Repression of ADH1 and ADH3 during zinc deficiency
by Zap1-induced intergenic RNA transcripts. EMBO J. 25:5726-5734
(2006).
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