Control of Gene Expression

Flashcards covering the key concepts and terminology regarding control of gene expression.

Gene Expression

The process by which information from a gene is used to synthesize a functional gene product, often proteins.

Transcriptional Control

The most common point of control in gene expression where molecules bind to DNA and/or polymerase.

Positive Regulation

A process where bound activator proteins promote transcription by enhancing the ability of RNA polymerase to bind.

Negative Regulation

A process where bound repressor proteins prevent transcription by blocking access to the gene.

Ligand

A molecule that binds to another (usually larger) molecule; in gene regulation, it activates or represses regulatory proteins.

Repressor Protein

A protein that binds to operator regions within a promoter to prevent transcription.

Activator Protein

A protein that binds to DNA to facilitate the transcription of a gene.

Lac Operon

A group of genes involved in lactose metabolism that is regulated based on the presence of glucose and lactose.

cAMP (cyclic adenosine monophosphate)

A regulatory molecule that influences the lac operon; its levels are inversely related to glucose concentration.

Eukaryotic Transcription Factors

Complex proteins that assist in the recruitment of RNA polymerase to genes, having both general and gene-specific roles.

Chromatin Structure

The arrangement of DNA and histone proteins that impacts gene accessibility for transcription.

Corepressor

A protein that represses gene expression by inhibiting the activity of an activator.

Coactivator

A protein that increases gene expression by enhancing the activation abilities of transcription factors.

Allolactose

A derivative of lactose that acts as a ligand by binding to the repressor protein, changing its conformation.

Transcription Activation

The process of initiating the synthesis of RNA from DNA, often facilitated by transcription factors and coactivators.