Chap 15: Gene regulation in eukaryotes

gene regulation

the phenomenon in which the level of gene expression can vary under different conditions.

transcription factors

a category of proteins that influence the ability of RNA polymerase to transcribe DNA into RNA.

domain

a region of a protein that has a specific function

motif

the name given to an amino acid sequence or domain that has a very similar structure and function in many proteins

homodimer

a combined structure (a dimer) formed when two polypeptides coded by the same gene bind to each other.

heterodimer

a combined structure (a dimer) formed when two polypeptides coded by different genes bind to each other.

up regulation

genetic regulation that leads to an increase in gene expression.

down regulation

genetic regulation that leads to a decrease in gene expression.

closed conformation

a conformation of chromatin that cannot be transcribed and may be tightly packed.

open conformation

a loosely packed structure of chromatin that can be transcribed.

chromatin remodeling

changes in chromatin structure that are due to the action of chromatin-remodeling complexes and that affect the positions and/or compositions of nucleosomes.

DNA translocase

a catalytic ATPase subunit that moves along the DNA. It is a component of chromatin-remodeling complexes.

histone acetyltransferase

an enzyme that attaches an acetyl group to the amino-terminal tail of a histone protein.

DNA methylation

a regulatory mechanism in which an enzyme covalently attaches a methyl group (—CH₃) to a base in DNA