Chapter 10 Regulation of Transcription Initiation Copyright c

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Chapter 10 Regulation of Transcription Initiation Copyright (c) by W. H. Freeman and Company

Chapter 10 Regulation of Transcription Initiation Copyright (c) by W. H. Freeman and Company

10. 1 Bacterial gene control: the Jacob. Monod model Figure 10 -2 Copyright (c)

10. 1 Bacterial gene control: the Jacob. Monod model Figure 10 -2 Copyright (c) by W. H. Freeman and Company

10. 1 Experimental evidence for cis-acting DNA sequences Figure 10 -3 Copyright (c) by

10. 1 Experimental evidence for cis-acting DNA sequences Figure 10 -3 Copyright (c) by W. H. Freeman and Company

10. 1 Experimental evidence for transacting genes/proteins Figure 10 -4 Copyright (c) by W.

10. 1 Experimental evidence for transacting genes/proteins Figure 10 -4 Copyright (c) by W. H. Freeman and Company

10. 2 Bacterial transcription initiation z RNA polymerase initiates transcription of most genes at

10. 2 Bacterial transcription initiation z RNA polymerase initiates transcription of most genes at a unique DNA position lying upstream of the coding sequence z The base pair where transcription initiates is termed the transcription-initiation site or start site z By convention, the transcription-initiation site in the DNA sequence is designated +1, and base pairs extending in the direction of transcription (downstream) are assigned positive numbers which those extending in the opposite direction (upstream) are assigned negative numbers z Various proteins (RNA polymerase, activators, repressors) interact with DNA at or near the promoter to regulate transcription initiation Copyright (c) by W. H. Freeman and Company

10. 2 DNase I footprinting assays identify protein-DNA interactions Figure 10 -6 Copyright (c)

10. 2 DNase I footprinting assays identify protein-DNA interactions Figure 10 -6 Copyright (c) by W. H. Freeman and Company

10. 2 Gel-shift assays identify protein-DNA interactions Figure 10 -7 Copyright (c) by W.

10. 2 Gel-shift assays identify protein-DNA interactions Figure 10 -7 Copyright (c) by W. H. Freeman and Company

10. 2 The footprint of RNA polymerase and lac repressor on the lac control

10. 2 The footprint of RNA polymerase and lac repressor on the lac control region Figure 10 -8 Copyright (c) by W. H. Freeman and Company

10. 2 The lac control region contains three critical cis-acting sites Figure 10 -9

10. 2 The lac control region contains three critical cis-acting sites Figure 10 -9 Copyright (c) by W. H. Freeman and Company

10. 2 RNA polymerase binds to specific promoter sequences to initiate transcription Each subunit

10. 2 RNA polymerase binds to specific promoter sequences to initiate transcription Each subunit has a specific function Figure 10 -10 Copyright (c) by W. H. Freeman and Company

10. 2 Differences in E. coli promoter sequences affect the frequency of transcription initiation

10. 2 Differences in E. coli promoter sequences affect the frequency of transcription initiation Copyright (c) by W. H. Freeman and Company Figure 10 -11

10. 2 Most operator sequences are short inverted repeats The lac operator Figure 10

10. 2 Most operator sequences are short inverted repeats The lac operator Figure 10 -12 Copyright (c) by W. H. Freeman and Company

10. 2 Most bacterial repressors are dimers containing helices that insert into adjacent major

10. 2 Most bacterial repressors are dimers containing helices that insert into adjacent major grooves of operator DNA Figure 10 -13 Copyright (c) by W. H. Freeman and Company

10. 2 Ligand-induced conformational changes alter affinity of many repressors for DNA Tryptophan binding

10. 2 Ligand-induced conformational changes alter affinity of many repressors for DNA Tryptophan binding induces a conformational change in the trp aporepressor Figure 10 -14 Copyright (c) by W. H. Freeman and Company

10. 2 Positive control of the lac operon is exerted by c. AMP-CAP =

10. 2 Positive control of the lac operon is exerted by c. AMP-CAP = catabolite activator protein Figure 10 -16 Copyright (c) by W. H. Freeman and Company

10. 2 Cooperative binding of c. AMP-CAP and RNA polymerase to the lac contol

10. 2 Cooperative binding of c. AMP-CAP and RNA polymerase to the lac contol region activates transcription Figure 10 -17 Copyright (c) by W. H. Freeman and Company

10. 2 Transcription from some promoters is initiated by alternative sigma ( ) factors

10. 2 Transcription from some promoters is initiated by alternative sigma ( ) factors Copyright (c) by W. H. Freeman and Company

10. 2 Activation of 54 -containing RNA polymerase at gln. A promotor by Ntr.

10. 2 Activation of 54 -containing RNA polymerase at gln. A promotor by Ntr. C Figure 10 -19 Copyright (c) by W. H. Freeman and Company

10. 2 Visualization of DNA looping and interaction of bound Ntr. C and 54

10. 2 Visualization of DNA looping and interaction of bound Ntr. C and 54 - polymerase Figure 10 -20 Copyright (c) by W. H. Freeman and Company

10. 2 Many bacterial responses are controlled by two-component regulatory systems The Pho. R/Pho.

10. 2 Many bacterial responses are controlled by two-component regulatory systems The Pho. R/Pho. B two-component regulatory system in E. coli Figure 10 -21 Copyright (c) by W. H. Freeman and Company

La dmarche catchumnale 1 Initiation initiation chrtienne InitiationLa dmarche catchumnale 1 Initiation initiation chrtienne Initiation
Project Initiation Project Initiation Purpose of initiation phaseProject Initiation Project Initiation Purpose of initiation phase
Initiation of r DNA transcription Two transcription factorsInitiation of r DNA transcription Two transcription factors
Transcription Initiation Specific transcription factors activators or repressorsTranscription Initiation Specific transcription factors activators or repressors
Prokaryotic Transcription Both Eukaryotic Transcription Prokaryotic Transcription 1Prokaryotic Transcription Both Eukaryotic Transcription Prokaryotic Transcription 1
Lecture 2 12317 Transcription initiation and its RegulationLecture 2 12317 Transcription initiation and its Regulation
Regulation after initiation Antitermination of transcription l AttenuationRegulation after initiation Antitermination of transcription l Attenuation
Transcription Regulation Transcription Factor Motif Finding Xiaole ShirleyTranscription Regulation Transcription Factor Motif Finding Xiaole Shirley
Transcription Regulation Transcription Factor Motif Finding Xiaole ShirleyTranscription Regulation Transcription Factor Motif Finding Xiaole Shirley
Chapter 11 Transcription Initiation Complex Copyright Garland ScienceChapter 11 Transcription Initiation Complex Copyright Garland Science
Cytoplasmic regulation lifetime localization initiation Posttranscriptional regulation 1Cytoplasmic regulation lifetime localization initiation Posttranscriptional regulation 1
Cytoplasmic regulation lifetime localization initiation Posttranscriptional regulation mCytoplasmic regulation lifetime localization initiation Posttranscriptional regulation m
Regulation Splicing Replication Regulation Transcription DNA bases ARegulation Splicing Replication Regulation Transcription DNA bases A
Gene Expression Regulation Lesson 8 Transcription and regulationGene Expression Regulation Lesson 8 Transcription and regulation
Chapter 20 Initiation of transcription 20 1 IntroductionChapter 20 Initiation of transcription 20 1 Introduction
Chapter 20 Initiation of transcription 20 1 IntroductionChapter 20 Initiation of transcription 20 1 Introduction
Chapter 11 Assembly of the Transcription Initiation ComplexChapter 11 Assembly of the Transcription Initiation Complex
Chapter 11 Bacterial Transcription 11 1 Introduction TranscriptionChapter 11 Bacterial Transcription 11 1 Introduction Transcription
Transcription In this chapter we will describe TranscriptionTranscription In this chapter we will describe Transcription