How Do Sigma Factors Regulate Major Physiological Responses

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The Answer is One species can make several different sigma factors that help RNA polymerase find the beginnings of different subsets of genes. The different sigma factors help RNA polymerase recognize different classes of promoters and control genes involved in nitrogen metabolism, flagellar synthesis, heat, stress, starvation, sporulation, and other physiological responses. Organisms have protein sensors that monitor the environment. When necessary, they direct the cell to increase synthesis of the appropriate sigma factor. Accumulation of specialty sigma factors dislodge other sigma factors from RNA polymerase and redirect RNA polymerase to promoters for genes that can be used to solve the problem sensed by the protein sensors. The cell can control physiological responses by regulating when a specific sigma factor accumulates.

How Do Sigma Factors Regulate Major Physiological Responses

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