2/21: 261-268

gene expression

The process by which cells selectively direct the synthesis of many proteins and RNAs encoded in their genome.

cell differentiation

The process through which cells become specialized in structure and function.

promoter

A DNA sequence that initiates the transcription of a particular gene.

transcription regulator

Proteins that bind to regulatory DNA sequences to control gene transcription.

operon

A cluster of genes regulated together, transcribed as a single mRNA molecule in bacteria.

repressor protein

A type of regulatory protein that suppresses the expression of a gene.

activator protein

A transcription factor that increases gene transcription by binding to specific DNA sequences.

mRNA

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

post-transcriptional control

Regulation of gene expression that occurs after RNA has been synthesized.

extracellular cues

Signals from the environment that can influence gene expression in cells.

mass spectrometry

An analytical method used to measure the mass-to-charge ratio of ions, often used to analyze proteins.

chromatin

A combination of DNA and protein found in the nucleus of eukaryotic cells that packages DNA into a compact, dense shape.

allosteric protein

A protein whose function is regulated by the binding of a molecule at a site other than the active site.

RNA polymerase

An enzyme that synthesizes RNA from a DNA template.

gene transcription

The process by which a specific segment of DNA is copied into RNA.

signal transduction

The process by which a cell responds to substances outside its membrane.

nucleotide sequence

The order of nucleotides in a DNA or RNA molecule.

homeodomain

A specific protein motif found in many eukaryotic transcription factors that enables DNA binding.

specificity of protein-DNA interaction

The precise binding of proteins to particular DNA sequences to regulate gene expression.

biochemical pathway

A series of chemical reactions occurring within a cell.

differentiated cell

A mature cell that has acquired specific functional or structural characteristics.