Cellular and Molecular Biology

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Bacterial Promoter Recognition


In bacterial genomes, different sets of genes may be transcribed under different conditions, often in response to changing environmental​ conditions, such as high temperature. The set of genes that is expressed together have similar gene promoters, DNA sequences that are found upstream from the gene and serve to aid in recognition of where transcription should begin.

How are these different sets of gene promoters generally recognized?


The cell groups all genes to be expressed together following a single promoter, with a unique promoter for every such set of genes.


The cell has multiple types of RNA polymerases to allow recognition of different promoters.


The cell has multiple transcription factors to allow recognition of different promoters.


The cell has a single type of RNA polymerase but one of its subunits is variable to allow recognition of different promoters.