HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

J. Biol. Chem., Vol. 276, Issue 12, 8979-8986, March 23, 2001

This Article Full Text Full Text (PDF) All Versions of this Article: 276/12/8979    most recent M009587200v1 Submit a Letter to Editor Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Wang, L. Articles by Gralla, J. D. Search for Related Content PubMed PubMed Citation Articles by Wang, L. Articles by Gralla, J. D. Social Bookmarking                      What's this?

Roles for the C-terminal Region of Sigma 54 in Transcriptional Silencing and DNA Binding^*

Lei Wang and Jay D. Gralla

From the Department of Chemistry and Biochemistry and the Molecular Biology Institute, University of California, Los Angeles, Los Angeles, California 90095-1569

Twenty-one conserved positively charged and aromatic amino acids between residues 331 and 462 of sigma 54 were changed to alanine, and the mutant proteins were studied by transcription, band shift analysis, and footprinting in vitro. A small segment corresponding to the rpoN box was found to be most important for binding duplex DNA. Two amino acids, 52 residues apart, were found to be critical for maintaining transcriptional silencing in the absence of activator. These two activator bypass mutants and several other mutants failed to bind the type of fork junction DNA thought to be required to maintain silencing. The two bypass mutants showed a binding pattern to DNA probes that was unique, both in comparison to other C-terminal mutants and to previously known N-terminal bypass mutants. On this basis, a model is proposed for the role of the C terminus and the N terminus of sigma 54 in enhancer-dependent transcription.

CiteULike

Complore

Connotea

Del.icio.us

Digg

Reddit

Technorati

This article has been cited by other articles:

				Y. Xiao, S. R. Wigneshweraraj, R. Weinzierl, Y.-P. Wang, and M. Buck Construction and functional analyses of a comprehensive {sigma}54 site-directed mutant library using alanine-cysteine mutagenesis Nucleic Acids Res., May 27, 2009; (2009) gkp419v1. [Abstract] [Full Text] [PDF]

				R. N. Leach, C. Gell, S. Wigneshweraraj, M. Buck, A. Smith, and P. G. Stockley Mapping ATP-dependent Activation at a {sigma}54 Promoter J. Biol. Chem., November 3, 2006; 281(44): 33717 - 33726. [Abstract] [Full Text] [PDF]

				S. Poggio, A. Osorio, G. Dreyfus, and L. Camarena Transcriptional Specificity of RpoN1 and RpoN2 Involves Differential Recognition of the Promoter Sequences and Specific Interaction with the Cognate Activator Proteins J. Biol. Chem., September 15, 2006; 281(37): 27205 - 27215. [Abstract] [Full Text] [PDF]

				M. Doucleff, L. T. Malak, J. G. Pelton, and D. E. Wemmer The C-terminal RpoN Domain of {sigma}54 Forms an Unpredicted Helix-Turn-Helix Motif Similar to Domains of {sigma}70 J. Biol. Chem., December 16, 2005; 280(50): 41530 - 41536. [Abstract] [Full Text] [PDF]

				P. C. Burrows, K. Severinov, A. Ishihama, M. Buck, and S. R. Wigneshweraraj Mapping {sigma}54-RNA Polymerase Interactions at the -24 Consensus Promoter Element J. Biol. Chem., August 8, 2003; 278(32): 29728 - 29743. [Abstract] [Full Text] [PDF]

				S. R. Wigneshweraraj, P. Casaz, and M. Buck Correlating protein footprinting with mutational analysis in the bacterial transcription factor {sigma}54 ({sigma}N) Nucleic Acids Res., February 15, 2002; 30(4): 1016 - 1028. [Abstract] [Full Text] [PDF]