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13.5: Introduction to Prokaryotic Gene Regulation

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    43708
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    Discuss different components of prokaryotic gene regulation

    The DNA of prokaryotes is organized into a circular chromosome supercoiled in the nucleoid region of the cell cytoplasm. Proteins that are needed for a specific function are encoded together in blocks called operons. For example, all of the genes needed to use lactose as an energy source are coded next to each other in the lactose (or lac) operon.

    In prokaryotic cells, there are three types of regulatory molecules that can affect the expression of operons: repressors, activators, and inducers. Repressors are proteins that suppress transcription of a gene in response to an external stimulus, whereas activators are proteins that increase the transcription of a gene in response to an external stimulus. Finally, inducers are small molecules that either activate or repress transcription depending on the needs of the cell and the availability of substrate.

    What You’ll Learn to Do

    • Understand the basic steps in gene regulation in prokaryotic cells
    • Explain the roles of repressors in negative gene regulation
    • Explain the role of activators and inducers in positive gene regulation

    Learning Activities

    The learning activities for this section include the following:

    • Gene Regulation in Prokaryotes
    • Repressors
    • Activators and Inducers
    • Self Check: Prokaryotic Gene Regulation

    Contributors and Attributions

    CC licensed content, Original
    • Outcome: Prokaryotic Gene Regulation. Provided by: Lumen Learning. License: CC BY: Attribution
    CC licensed content, Shared previously

    13.5: Introduction to Prokaryotic Gene Regulation is shared under a not declared license and was authored, remixed, and/or curated by LibreTexts.

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