JUDITH R. LEVIN
Research Interests: Biochemistry
of Protein-DNA Interactions,
Structure-Function
Relationships in Transcription
Complexes
of E. coli RNA
Polymerase, Nucleic
Acid
Structure and Enzymology
Research in Progress:
The expression of genes in living
cells is carried out by proteins that can recognize and bind to specific
nucleotide sequences in DNA. These proteins then act in various ways to extract
genetic information from the DNA in a highly regulated manner. My research focuses
in general on understanding the mechanisms by which DNA-binding proteins are
able to recognize specific signals in DNA and carry out their specific
functions. Recognition may involve chemical as well as structural features of
DNA, such as its ability to be deformed into bent or kinked conformations.
These features of DNA may also play important roles in the subsequent action of
DNA-binding proteins during gene expression. My experimental approach uses
chemical techniques to investigate the structures of protein-DNA complexes in
order to gain insight into the mechanisms by which they function.
Of particular interest to me
(among other DNA-binding proteins) is an enzyme called RNA polymerase, which
binds to DNA and moves along it, transcribing the genetic information in the
DNA into a corresponding RNA molecule.
Very little is known about the structure of the transcribing enzyme
complex or the mechanics of its motion as it progresses along a DNA molecule. Investigation of this process by the
chemical techniques mentioned above is an important step toward the ultimate
goal of understanding how this biological "machine" may be regulated
in living cells.
Representative Student
Independent Research Projects:
Carolyn Pizoli Generation
of Transcription Templates Using Polymerase Chain
Reaction.
Meredith Brown Characterization
of Steady-State Transcription of Bent DNA Templates
by E. coli RNA
Polymerase.
Jennifer Galli The
Effect of DNA Bending on Transcription by Bacteriophage RNA Polymerases: Template Construction.
Cynthia Polhamus Kinetics of
Single-Round Transcription of Bent DNA by E. coli RNA
Polymerase: Analysis by Gel
Electrophoresis
JUDITH
R. LEVIN (cont.)
Representative Student
Independent Research Projects (cont.)
Anna Odnopozova Characterization
of Pausing by E. coli RNA Polymerase at
A-tract-Induced
Bends in DNA
Carolyn Mochel The
Effect of DNA Bending on Transcription by Bacteriophage
RNA
Polymerases: Template Construction and Preliminary Analysis
Stephanie Solter The
Effects of Single Template Nucleoside Gaps on
Transcription
Initiation by E. coli RNA Polymerase
Genevieve Monsees Statistical Analysis of Data on the
Kinetics of Transcription Initiation
by E. coli RNA Polymerase
Representative Publications:
Levin, J.R., Krummel, B. and
Chamberlin, M.J. (1987) Isolation and Properties of Transcribing Ternary
Complexes of Escherichia coli RNA Polymerase
Positioned at a Single Template Base. J. Mol. Biol. 196: 85-100.
Levin, J.R., Burkhoff, A.M. and
Tullius, T.D. (1991) "Using the Chemistry of the Hydroxyl Radical to
Determine Structural Details about DNA and Protein-DNA
Complexes". In A Laboratory Guide to In Vitro
Studies of Protein-DNA Interactions
(J.P. Jost and H.P. Saluz, eds.), Biomethods
(Birkhauser Verlag)
5: 133-144.
Dixon, W.J., Hayes, J.J., Levin,
J.R., Weidner, M.F., Dombroski, B.A. and Tullius, T.D. (1991) Hydroxyl Radical Footprinting of
Protein-DNA Complexes. Meth.
Enzymol.
208: 380.
Draganescu, A., Levin, J.R. and Tullius,
T.D. (1995) Homeodomain Proteins: What Governs Their Ability to Recognize
Specific DNA Sequences? J. Mol.
Biol. 250: 595-608.
Levin, J.R., Blake, J.J., Ganunis, R.A. and
Tullius, T.D. (2000) The Roles of Specific Template Nucleosides in the Formation
of Stable Transcription Complexes by Escherichia coli RNA Polymerase. J. Biol. Chem. 275: 6885 - 6893.