Molecular Genetics Bio350516

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Molecular Genetics Bio350/516 Lecture 17, 3/28/06
I. Chapter 10 (continued) A. Promoters
1. Pol II (class II) a. Linker
scanning 2. Pol I (class I) 3.
Pol III (class III) B. Enhancers and
Silencers
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Class II Promoters mRNA genes
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Figure 10.20
Composite of a Class II promoter Not all
elements are in all class II promoters
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TATA Box Function
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Figure 10.21
Role of the TATA box in positioning the start site
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Discovery of GC Box Elements
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Linker-Scanning
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Figure 10.22
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Frog Oocytes
Diameter of 1.0 1.2 mm
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GC box
TATA box
GC box
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Class I Promoters rRNA genes
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Figure 10.24
Linker-Scanning of human rRNA gene TXN
Transcription
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Figure 10.25
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Class III Promoters 5S rRNA tRNA genes
(classical) (promoters are internal) nonclassical
genes (some look like Class II promoters)
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Figure 10.26
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Figure 10.27a
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Figure 10.27b
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Figure 10.28
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Enhancers
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Figure 10.30
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Figure 10.31a
Intron
Exons
Exons
X XbaI site
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Figure 10.31b
Protein Levels
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Figure 10.31c
Transcript Levels
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Figure 10.32
Orientation and Position Independent Enhancer