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Terri Goss Kinzy
Professor
UMDNJ - RWJMS
Dept of Molecular Genetics and Microbiology
Room R709
Piscataway. NJ 08854
(732) 235-5450
FAX - 5223
kinzytg@umdnj.edu |
Regulation and mechanism of gene expression and protein synthesis
and links to the cytoskeleton, infectious disease targets in translation
The goal of the work in our laboratory is to understand the structural and
functional basis of post-transcriptional mechanisms that regulate gene
expression and targets of this process for fighting infectious diseases. The
components of the Translation Elongation apparatus in yeast, from soluble
protein factors to the ribosome, allow an integrated approach to these
questions. These components are targets for antibiotics and antifungals,
mutant forms and inappropriate expression of these proteins are found in
several human carcinomas, and mutations in several components affect the
accuracy and efficiency of protein synthesis and viral replication.
We are applying complementary genetic. Molecular, biochemical and structural
techniques to dissect the mechanism of events occurring during protein
synthesis. These include probing the physical and functional interaction of
Elongations Factors (eEFs) with other factors that regulate gene expression.
and the interaction between the G-proteins in elongation with the ribosome.
The eEF1 protein complex is prototypical of all G-proteins. such as the
oncogene Ras. and as such is regulated by a classic "GTPase" switch
mechanism. The GTP-dependent activity of eEF1A is to deliver aminoacyl-tRNA
to the ribosome and sense the accuracy of this process. The guanine
nucleotide exchange factor (GEF) eEF1Balpha is essential in yeast and
responsible for catalyzing the exchange of GDP for GTP to maintain the pool
of active protein. Using a genetic system devoid of the eEF1Balpha protein
allows us to manipulate eEF1A without its GEF to understand the regulation
of G-protein activity and mutant forms of eEF1Balpha allow us to dissect the
mechanism of guanine nucleotide exchange in vitro and the consequences of
changes in this protein's activity in vivo. Lastly. the eEF1Bgamma subunit
affects the sensitivity of the cell to oxidative stress and vacuolar
function. Current work is addressing the implications of this finding in
post-transcriptional control. In addition, eEF1A is an actin binding and
bundling protein. Our work now shows an integrated model is emerging for
organizing and regulating proteins synthesis in vivo. This actin binding is
separate from the elongation activity and a target for 2 drugs we are
studying for multiple medical applications.
Integrating an analysis of the two other factors involved in elongation, the
translocase for the growing peptide chain eEF2 and the fungal specific
factor eEF3 allows us to fully dissect the elongation cycle and to better
understand their potential as drug targets. eEF2 is the target for
diphtheria and pseudomonas toxins, and our work is addressing how these
toxins attach the host cell. In addition, new work is addressing the
association of eEF3 and the ribosome to determine how this interaction can
be used for antifungal development. Using mutants as well as eEF3 from
pathogenic fungal species and our structural data we are working towards
developing targets for new drugs against this fungal specific essential
proteins.
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