Gene regulation in prokaryotes

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Gene regulation in prokaryotes

• March 27, 2006

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Inducible transcription lac operon
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Inducible transcription lac operon
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Transcription termination by attenuation trp
operon
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Transcription termination by attenuation
Two possible base-pairing schemes within the mRNA
at the beginning of the trp operon
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Transcription termination by attenuation
Not enough tryptophan amino acids causes ribosome
to stall on the mRNA ? allows pre-emptor stemloop
to form ? termination does not occur
Moving ribosome ? pre-emptor structure does not
form terminator stemloop forms terminates
transcription of the rest of the mRNA
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Regulation in phage lambda(?)
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Regulation in phage lambda(?)