Control of Prokaryotic Gene Expression

Flashcards covering key concepts in the control of prokaryotic gene expression, including operons, gene regulation mechanisms, and relevant terminologies.

Housekeeping Exam

An exam scheduled for revision topics including Chapters 15, 16, 17, and a partial on 25.

Constitutive gene expression

Gene expression that is continuously expressed under normal cellular conditions.

Positive control

A mechanism that stimulates gene expression.

Negative control

A mechanism that inhibits gene expression.

Structural genes

Genes that encode proteins for metabolism, biosynthesis, or cellular structures.

Regulatory genes

Genes that encode products affecting the transcription and translation of other sequences.

Operon

A single transcriptional unit that includes a promoter, operator, and series of structural genes.

Inducible operon

An operon where transcription is usually off and must be induced (turned on).

Repressible operon

An operon that is normally on and must be repressed (turned off).

Regulator gene

A gene that encodes a regulatory protein affecting the operon function but is not part of the operon.

Corepressor

A small molecule that binds to the repressor, making it capable of binding to the operator to inhibit transcription.

Transcription

The process of copying a segment of DNA into mRNA.

Translation

The process by which ribosomes synthesize proteins using the information from mRNA.

Amino acid

The building block of proteins, coded by codons.

DNA-binding protein

Proteins that interact with DNA to regulate gene expression.

Negative inducible operons

Operons that are off due to an active repressor that can be induced to allow transcription.

Negative repressible operons

Operons that are on due to an inactive repressor that can be activated by a corepressor.

Functional domain

Regions of a protein that have distinct functional roles, such as binding to a specific target.

Motif

A simple structure in the DNA-binding domain that fits into the major groove of DNA.

Hydrogen bonds

Weak bonds that play a key role in the interaction between DNA-binding proteins and DNA.