AP BIO - Gene Regulation/ Viruses

Capsid

The protein shell that surrounds and protects a virus’s genetic material

Operon

A group of genes controlled together by one regulatory system in prokaryotes

Repressor

A protein that binds to DNA and blocks transcription of a gene

Lytic cycle

A viral cycle where the virus copies itself and destroys the host cell

Lysogenic cycle

A viral cycle where viral DNA stays in the host cell without killing it right away

Prophage

Viral DNA that is integrated into a bacterial chromosome

Provirus

Viral DNA that is integrated into a eukaryotic host genome

Virion

A complete, infectious virus particle outside a host cell

Prion

An infectious protein that causes disease by misfolding other proteins

Transformation

The uptake of foreign DNA from the environment by a cell

cAMP

A signaling molecule that helps activate gene expression when glucose is low

DNA methylation

A chemical modification of DNA that usually reduces gene expression

Histone acetylation

A modification of histone proteins that makes DNA easier to transcribe

Control elements

DNA sequences that regulate when and how much a gene is expressed

Ras gene

A gene involved in cell growth signaling that can cause cancer when mutated

Gene amplification

An increase in the number of copies of a gene in a cell

Enhancers

DNA regions that increase transcription of a gene by binding activator proteins

Oncogenes

Cancer-causing genes that promote uncontrolled cell division

Multigene family

A group of related genes with similar sequences and functions

Pseudogene

A gene-like sequence that no longer functions

Heterochromatin

Tightly packed DNA that is usually not transcribed

Retrotransposons

Genetic elements that copy themselves through an RNA intermediate

Satellite DNA

Highly repetitive DNA sequences often found near centromeres and telomeres