A regulon is a set of genes controlled by a. one type of regulator of transcription. b. two or more different alternative sigma proteins. c. many different types of promoters. d. glucose.

Verified step by step guidance

1. Identify the key term: A regulon is a collection of genes or operons that are regulated as a unit, typically under the control of the same regulatory protein.
2. Understand the options: Analyze each option to see which best fits the definition of a regulon.
3. Option a suggests that a regulon is controlled by one type of regulator of transcription, which aligns with the definition of a regulon being regulated by a common regulatory mechanism.
4. Option b, c, and d introduce multiple regulators, different promoters, or a specific substance (glucose) which do not strictly adhere to the concept of a regulon being controlled by a single type of regulatory protein.
5. Conclude that the correct answer is a. one type of regulator of transcription, as it best fits the definition of a regulon.

Key Concepts

Regulon

A regulon is a collection of genes that are regulated together by a common regulatory protein, often in response to specific environmental conditions. This allows for coordinated expression of genes that contribute to a particular biological function or response, such as metabolism or stress adaptation.

Transcription Regulation

Transcription regulation involves mechanisms that control the transcription of genes, determining when and how much of a gene product is made. This can occur through various factors, including transcription factors, which can either promote or inhibit the binding of RNA polymerase to DNA, thus influencing gene expression.

Sigma Factors

Sigma factors are proteins that bind to RNA polymerase and direct it to specific promoters, initiating transcription. Different sigma factors can recognize different sets of promoters, allowing bacteria to adapt their gene expression in response to environmental changes, which is essential for survival and growth.