Gene Expression and Regulation

This set of flashcards contains vocabulary related to gene expression and regulation, including definitions and important concepts essential for understanding molecular biology.

Central Dogma

The process of genetic information flow from DNA to RNA to protein.

mRNA

Messenger RNA, a type of RNA that conveys genetic information from DNA to the ribosome.

Transcription

The process of copying a segment of DNA into RNA.

Translation

The process in which ribosomes synthesize proteins using mRNA.

Introns

Non-coding sequences in RNA that are removed during RNA processing.

Exons

Coding sequences in RNA that are retained and translated into proteins.

Gene Expression

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

Ribosome

Cellular organelle where translation occurs; synthesizes proteins.

Polypeptides

Chains of amino acids that make up proteins.

Regulatory Proteins

Proteins that influence the transcription of specific genes by binding to nearby genes.

Promoter

A DNA sequence that initiates transcription of a particular gene.

Operon

A cluster of genes under the control of a single promoter.

Repressor

A protein that inhibits gene expression by binding to the operator.

Activator

A protein that increases gene expression by helping RNA polymerase to bind to the promoter.

Transcription Factors

Proteins that bind to specific DNA sequences to regulate transcription.

RNA Polymerase

The enzyme responsible for synthesizing RNA from a DNA template during transcription.

Chromatin

The complex of DNA and proteins that makes up eukaryotic chromosomes.

Homeostasis

The maintenance of stable internal conditions, which genes may regulate.

Histone

Proteins around which DNA is coiled to form chromatin.

DNA Binding Motif

A structural feature of regulatory proteins that enables them to bind to DNA.

Epigenetics

The study of heritable changes in gene expression that do not involve changes to the underlying DNA sequence.

DNA Methylation

The addition of methyl groups to DNA, affecting gene expression without altering the sequence.

Histone Modification

The addition or removal of chemical groups to histones, affecting chromatin structure and gene expression.

Enhancer

A regulatory DNA sequence that can increase transcription levels of genes.

Silencer

A DNA sequence that can repress gene transcription.

Alternative Splicing

The process by which different combinations of exons are joined together to produce different mRNA molecules from the same gene.

Post-Transcriptional Regulation

Regulation of gene expression after transcription has occurred but before translation.

Post-Translational Modification

Chemical changes to protein that may alter its function, localization, or stability.

mRNA Splicing

The process of removing introns from pre-mRNA and joining exons.

Polyadenylation

The addition of a poly-A tail to the 3' end of mRNA, enhancing stability and export from the nucleus.

Genome

The complete set of genes or genetic material present in a cell or organism.

Gene Regulation

The mechanisms that are used by cells to increase or decrease the production of specific gene products.

Effector Molecules

Small molecules that regulate the activity of repressors or activators.

Transcription Start Site

The nucleotide where RNA polymerase begins transcription.

Mediator Complex

A multiprotein complex that regulates gene expression by serving as a bridge between transcription factors and RNA polymerase.

TATA Box

A DNA sequence found in the promoter region indicating where a genetic sequence can be read and transcribed.

Identity of Cell Types

The unique expression profile of genes resulting in different types of cells.

Coordination of Gene Expression

The regulated expression of numerous genes simultaneously during processes such as development.

Functional Genes

Genes that encode proteins necessary for cellular function.

Gene Duplication

The process by which a region of DNA is duplicated, resulting in two copies of a gene.

Regulatory Gene

A gene that codes for a protein that interacts with the operator of a operon to regulate transcription.

Differential Gene Expression

The phenomenon where cells express different sets of genes, leading to diverse cell types.

Feedback Mechanisms

Processes that help regulate gene expression levels in response to the cell’s needs.

Phenotypic Changes

Observable traits that result from changes in gene expression.

Chromosomal Packaging

The organization of DNA into compact structures to fit within the nucleus.

Downstream

Referring to the direction along a DNA molecule that follows a given point.

Upstream

Referring to the direction along DNA that precedes a given point.

Lactose Operon

An operon that contains genes for the metabolism of lactose.

Tryptophan Operon

An operon that regulates the production of tryptophan based on availability.

Nucleotide Binding Site

A region in a protein where nucleotides can bind.

Ribosome Binding Site

The location on mRNA where ribosomes attach to initiate translation.

Protein Denaturation

The process by which proteins lose their native structure and function.

Phenomenon of mRNA Interference

Process by which RNA molecules inhibit gene expression or translation.

Protein Stability

The permanence of a protein's function and structure over time.

Short-lived Proteins

Proteins that are rapidly degraded within the cell.

Cellular Differentiation

The process by which a less specialized cell becomes a more specialized cell type.

Nucleus

Membrane-bound organelle that contains the cell's genetic material.

Cytoplasm

Gel-like substance within the cell membrane where organelles are suspended.

Genome Plasticity

The ability of a genome to adapt and change over time.

Functional Diversity of Proteins

The variety of functions that proteins can have due to their diverse structures.

Transcriptional Control

The regulation of gene transcription and RNA synthesis.

Cellular Environment

The conditions and materials surrounding a cell that affect its function.