Activation and Repression of Transcription by Differential Contact: Two Sides of a Coin

Activation and repression of transcription are primarily caused by gene regulatory proteins (activators and repressors), which act by binding to specific sites on DNA. The steps from initial binding of RNA polymerase to the elongating complex are characterized by many intermediates, each with a discrete structure, offering many mechanistic possibilities for regulator actions. It has been shown in some systems that the activator acts by helping RNA polymerase or other associated factors to bind (recruitment) and/or by influencing a postrecruitment step (isomerization, promoter clearance, etc.) (1Ptashne M. Gann A. Nature. 1997; 386: 569-577Crossref PubMed Scopus (929) Google Scholar, 2Malan T. Kolb A. Buc H. McClure W. J. Mol. Biol. 1984; 180: 881-909Crossref PubMed Scopus (158) Google Scholar, 3Dove S.L. Joung J.K. Hochschild A. Nature. 1997; 386: 627-630Crossref PubMed Scopus (226) Google Scholar, 4Menendez M. Kolb A. Buc H. EMBO J. 1987; 6: 4227-4234Crossref PubMed Scopus (58) Google Scholar, 5Sasse-Dwight S. Gralla J.D. Proc. Natl. Acad. S. A. PubMed Scopus Google Scholar, Proc. Natl. Acad. S. A. Scopus Google Scholar, J. PubMed Scopus Google the for to on the initial binding step of RNA that a step from the step are in act the of RNA polymerase to the are to steps that on initial binding M. Kolb A. Buc H. EMBO J. 1987; 6: 4227-4234Crossref PubMed Scopus (58) Google Scholar, 5Sasse-Dwight S. Gralla J.D. Proc. Natl. Acad. S. A. PubMed Scopus Google Scholar, Proc. Natl. Acad. S. A. Scopus Google Scholar, J. PubMed Scopus Google repression by the binding of RNA polymerase or in transcription to the promoter McClure J. Biol. PubMed Google Scholar, J. Mol. Biol. PubMed Scopus Google other in S. PubMed Scopus Google with RNA polymerase a step 1987; PubMed Scopus Google Scholar, J. A. PubMed Scopus Google Scholar, H. T. A. S. EMBO J. PubMed Scopus Google Scholar, M. M. M. EMBO J. 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Nature. PubMed Scopus Google It has been shown that transcription by the from T. Kolb A. Buc H. McClure W. J. Mol. Biol. 1984; 180: 881-909Crossref PubMed Scopus (158) Google that the and and with regulator and the of and the of that of The in and and by a and of by and PubMed Scopus Google Scholar, Proc. Natl. Acad. S. A. PubMed Scopus Google and by of the promoter A. PubMed Scopus Google W. T. PubMed Scopus Google on the other the regulator the regulator and the of The of The the the the for the of the and the RNA polymerase on of activator the of promoter by McClure J. Mol. Biol. PubMed Scopus Google Scholar, J. Mol. Biol. PubMed Scopus Google by the of of the to the the the complex and and of been that bind to to transcription and the of with RNA polymerase M. PubMed Scopus Google Scholar, M. PubMed Scopus Google of the of RNA polymerase been which specific on transcription that the and the M. H. PubMed Scopus Google of activator It acts the which a polymerase A. S. 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PubMed Scopus Google the of complex of transcription of gene transcription It that to in the RNA or which the of the regulator and some of the the to which the regulator and the regulatory Activation and repression of transcription are primarily caused by gene regulatory proteins (activators and repressors), which act by binding to specific sites on DNA. The steps from initial binding of RNA polymerase to the elongating complex are characterized by many intermediates, each with a discrete structure, offering many mechanistic possibilities for regulator actions. It has been shown in some systems that the activator acts by helping RNA polymerase or other associated factors to bind (recruitment) and/or by influencing a postrecruitment step (isomerization, promoter clearance, etc.) (1Ptashne M. Gann A. Nature. 1997; 386: 569-577Crossref PubMed Scopus (929) Google Scholar, 2Malan T. Kolb A. Buc H. McClure W. J. Mol. Biol. 1984; 180: 881-909Crossref PubMed Scopus (158) Google Scholar, 3Dove S.L. Joung J.K. Hochschild A. Nature. 1997; 386: 627-630Crossref PubMed Scopus (226) Google Scholar, 4Menendez M. Kolb A. Buc H. EMBO J. 1987; 6: 4227-4234Crossref PubMed Scopus (58) Google Scholar, 5Sasse-Dwight S. Gralla J.D. Proc. Natl. Acad. S. A. PubMed Scopus Google Scholar, Proc. Natl. Acad. S. A. Scopus Google Scholar, J. PubMed Scopus Google the for to on the initial binding step of RNA that a step from the step are in act the of RNA polymerase to the are to steps that on initial binding M. Kolb A. Buc H. EMBO J. 1987; 6: 4227-4234Crossref PubMed Scopus (58) Google Scholar, 5Sasse-Dwight S. Gralla J.D. Proc. Natl. Acad. S. A. PubMed Scopus Google Scholar, Proc. Natl. Acad. S. A. Scopus Google Scholar, J. PubMed Scopus Google repression by the binding of RNA polymerase or in transcription to the promoter McClure J. Biol. PubMed Google Scholar, J. Mol. Biol. PubMed Scopus Google other in S. PubMed Scopus Google with RNA polymerase a step 1987; PubMed Scopus Google Scholar, J. A. PubMed Scopus Google Scholar, H. T. A. S. EMBO J. PubMed Scopus Google Scholar, M. M. M. EMBO J. PubMed Scopus Google Scholar, M. M. M. Proc. Natl. Acad. S. A. PubMed Scopus Google Scholar, Proc. Natl. Acad. S. A. PubMed Scopus Google Scholar, J. 1997; PubMed Google some act activator in and in H. T. A. S. EMBO J. PubMed Scopus Google Scholar, M. M. M. Proc. Natl. Acad. S. A. PubMed Scopus Google the on the of some and of RNA polymerase been A. J. PubMed Google Scholar, S. PubMed Scopus Google or of transcription in the the of transcription by of RNA polymerase and/or by of in RNA polymerase by to the a polymerase a in transcription a for the of activator and of or of the of RNA complex by with the a that the of some in the of transcription a the of of RNA polymerase transcription in steps of RNA polymerase binding to the promoter to transcription been PubMed Scopus Google Scholar, Proc. Natl. 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Nature. PubMed Scopus Google It has been shown that transcription by the from T. Kolb A. Buc H. McClure W. J. Mol. Biol. 1984; 180: 881-909Crossref PubMed Scopus (158) Google that the and and with regulator and the of and the of that of The in and and by a and of by and PubMed Scopus Google Scholar, Proc. Natl. Acad. S. A. PubMed Scopus Google and by of the promoter A. PubMed Scopus Google W. T. PubMed Scopus Google on the other the regulator the regulator and the of The of The the the the for the of the and the RNA polymerase on of activator the of promoter by McClure J. Mol. Biol. PubMed Scopus Google Scholar, J. Mol. Biol. PubMed Scopus Google by the of of the to the the the complex and and of been that bind to to transcription and the of with RNA polymerase M. PubMed Scopus Google Scholar, M. PubMed Scopus Google of the of RNA polymerase been which specific on transcription that the and the M. H. PubMed Scopus Google of activator It acts the which a polymerase A. S. 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