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Dana Levasseur, Ph.D. (Full Member)
Assistant Professor, Department of
Internal Medicine, University of Iowa
http://www.int-med.uiowa.edu/Divisions/Immunology/Directory/DanaLevasseur.html
Research Interest:
Research in the Levasseur lab focuses on the derivation and manipulation of stem
cells for use in cell and genetic therapies to correct blood disorders.
Embryonic stem (ES) cells are endowed with two distinguishing properties, they
can regenerate themselves indefinitely (self-renewal) and simultaneously enable
development of all cells in the body (pluripotency). Broadly, the other
long-term objective of our research is to identify and characterize
transcription factors and nuclear proteins that regulate self-renewal and
pluripotency. In one project, we are investigating the transcriptional and
epigenetic regulation of the nuclear factors GDF3, Dppa3 and the transcription
factor Nanog. These genes lie in the same genomic region, or locus, and this
Nanog locus appears to constitute a functional module that is important for
pluripotency. Nanog locus gene expression and chromatin structure are both
highly dependent on the expression of another pluripotency transcription factor,
Oct4. Recent discoveries have shown that Oct4 and Nanog are amongst a small
group of genes that can reset the developmental clock and reprogram adult cells
to an embryonic pluripotent state. The study of these induced pluripotent stem
(iPS) cells will be essential for shedding insight on the molecular machinery
responsible for the maintenance of self-renewal and pluripotency. Using a
combinatorial approach, we are investigating the genetic changes that enable
reprogramming to a pluripotent state. A better understanding of iPS cells will
be essential for their eventual use toward the correction of hematologic and
other disorders in human patients. Another topic of study in the laboratory is
determining how pluripotency factor bound enhancers bridge long distance
interactions within the Nanog locus, and how this regulates gene expression.
Using methods to analyze chromatin structure in pluripotent cell populations, we
are studying whether genes that occupy collinear positions within the genome may
also exhibit transcriptional co-regulation. To study these questions and achieve
our goals, we are employing the tools of molecular biology, genetics,
biochemistry and proteomics. Additionally, we are using conditional gene
targeting approaches and RNA interference (RNAi) to engineer new ES cell lines
and mouse models.