Transcription termination is a process whereby the elongation complex dissociates into RNA transcript, DNA template, and RNA polymerase (RNAP) in response to intrinsic DNA signals or specific factors. Both, intrinsic termination and factor-dependent termination are an integral part of the transcription cycle and play crucial role in regulating gene expression of bacteria and phages. Classical examples of such regulation include attenuation of transcription of biosynthetic operons and phage gamma-antitermination. The long-term objective of the proposed work is to provide a comprehensive structural and mechanistic description of intrinsic and Rho-dependent transcription termination processes in Escherichia coli and the mechanism of their positive and negative regulation by host factor NusA and phage XN protein, respectively. It is further proposed to examine the attenuation mechanism that controls nucleotide biosynthesis in Bacillus subtilis.
Specific aims are: Complete studies on the mechanism of intrinsic termination and its control by N. The general mechanism of intrinsic termination and its regulation by N and NusA is now understood. However important details of the process remain unresolved. These include the positioning of N, NusA, and other Nus factors in the elongation complex, conformational changes in RNAP that accompany the termination process, and the active role of certain RNAP domains in termination. Experiments are proposed to address those questions. Analyze the mechanism of Rho-dependent transcription termination and its control by N. The rearrangement of protein-RNA and protein-DNA contacts in the elongation complex during termination by Rho will be monitored. Experiments are proposed to determine the effect of gamma N antitermination factor on the protein-nucleic acids interactions in the Rho-termination complex. Analyze the termination control mechanism of purine operons in Bacilli. Experiments are proposed to examine the role of newly discovered """"""""riboswitches"""""""", i.e. natural regulatory RNA aptamers that directly sense small molecules, in regulation of purine operons in B.subtilis.

Agency
National Institute of Health (NIH)
Institute
National Institute of General Medical Sciences (NIGMS)
Type
Research Project (R01)
Project #
5R01GM058750-09
Application #
7162166
Study Section
Special Emphasis Panel (ZRG1-MBC-2 (01))
Program Officer
Tompkins, Laurie
Project Start
1999-01-01
Project End
2008-03-31
Budget Start
2007-01-01
Budget End
2008-03-31
Support Year
9
Fiscal Year
2007
Total Cost
$574,348
Indirect Cost
Name
New York University
Department
Biochemistry
Type
Schools of Medicine
DUNS #
121911077
City
New York
State
NY
Country
United States
Zip Code
10016
Epshtein, Vitaliy (2015) UvrD helicase: an old dog with a new trick: how one step backward leads to many steps forward. Bioessays 37:12-9
Epshtein, Vitaly; Kamarthapu, Venu; McGary, Katelyn et al. (2014) UvrD facilitates DNA repair by pulling RNA polymerase backwards. Nature 505:372-7
Svetlov, Vladimir; Nudler, Evgeny (2013) Basic mechanism of transcription by RNA polymerase II. Biochim Biophys Acta 1829:20-8
Nedialkov, Yuri A; Opron, Kristopher; Assaf, Fadi et al. (2013) The RNA polymerase bridge helix YFI motif in catalysis, fidelity and translocation. Biochim Biophys Acta 1829:187-98
Helmrich, Anne; Ballarino, Monica; Nudler, Evgeny et al. (2013) Transcription-replication encounters, consequences and genomic instability. Nat Struct Mol Biol 20:412-8
Nedialkov, Yuri A; Nudler, Evgeny; Burton, Zachary F (2012) RNA polymerase stalls in a post-translocated register and can hyper-translocate. Transcription 3:260-9
Hollands, Kerry; Proshkin, Sergey; Sklyarova, Svetlana et al. (2012) Riboswitch control of Rho-dependent transcription termination. Proc Natl Acad Sci U S A 109:5376-81
Svetlov, Vladimir; Nudler, Evgeny (2012) Unfolding the bridge between transcription and translation. Cell 150:243-5
Nudler, Evgeny (2012) RNA polymerase backtracking in gene regulation and genome instability. Cell 149:1438-45
Ó Maoiléidigh, Dáibhid; Tadigotla, Vasisht R; Nudler, Evgeny et al. (2011) A unified model of transcription elongation: what have we learned from single-molecule experiments? Biophys J 100:1157-66

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