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28 votes
1. You have set up a cell-free transcription system in a test tube. By mixing DNA, RNA polymerase, sigma factors, ribonucleotides and other essential substances you are able to make mRNAs identical to those made under a variety of conditions in the cells from which these components were isolated. What would happen if you were able to remove the sigma factor first added to the tube and replace it with another sigma factor

User Derian
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1 Answer

16 votes
16 votes

Answer:

Different messenger RNAs (mRNAs) would have been produced

Step-by-step explanation:

Sigma factors are protein subunits that form bacterial RNA polymerases and they are responsible to initiate RNA synthesis. The number of sigma factors is variable between different bacterial species. For example, Escherichia coli contains seven sigma factors, while Bacillus subtilis has at least 17 sigma factors, which control the transcription of different genes. These factors determine the specificity of the RNA polymerase to the target gene promoter regions and then control transcription initiation.

User Arthur Shinkevich
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