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Gene regulation in prokaryotes. March 27, 2006. Inducible transcription: lac operon. Inducible transcription: lac operon. Transcription termination by attenuation: trp operon. Transcription termination by attenuation.
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Gene regulation in prokaryotes March 27, 2006
Transcription termination by attenuation Two possible base-pairing schemes within the mRNA at the beginning of the trp operon
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