Chapter Nineteen: Gene Regulation in Eukaryotes Flashcards
what are at least five ways to regulate gene expression in a eukaryote
- transcription initiation
- transcription processing
- mRNA export from the nucleus
- translation of mRNA
- protein localization
- protein modification
compared to prokaryotes, eukaryotes have additional levels of complexity for controlling ___
gene expression
___ in eukaryotes often makes DNA unavailable to transcription machinery
chromatin structure
additional ___ processing events occur in eukaryotes
RNA
in eukaryotes, transcription occurs in the ___ and translation occurs in the ___
nucleus
cytoplasm
gene regulation controls ___ into hundreds of specialized cell types
cell differentiation
RNA pol I transcribes ___
RNA pol II transcribes ___
RNA pol III transcribes ___
rRNA genes
genes that encode proteins
tRNA genes and some small RNAs
DNA sequence that is usually directly adjacent to the gene, where RNA polymerase binds
promoter
promoters in eukaryotes often have a ___
TATA box
genes that are expressed at low levels all the time
housekeeping genes
genes that make cells unique, expression is cell or time specific
luxury genes
there are ___ cell types in humans
200
a regulatory site that can be far away from the gene
enhancer
enhancers are binding sites for ___
transcription factors
enhancers still function when moved to different positions relative to promoter because of ___
flexibility of DNA
a ___ can tell you the location and time of gene expression
reporter gene
three general reporter genes
- GFP
- LacZ
- luciferase
GFP is ___ and has ___ sensitivity
fluorescent
high
lacZ is ___ and has ___ sensitivity
chromatogenic
medium
luciferase is ___ and has ___ sensitivity
luminescent
low
transcription factors are ___ that act in ___ to control ___
proteins
trans
transcription initiation
transcription factors bind to ___ and ___
promoters and enhancers
transcription factors recruit ___ to influence transcription
other types of proteins
three types of transcription factors
- basal factors
- activators
- repressors
basal factors bind to ___ of protein-encoding genes
promoters
a complex of more than 20 proteins needed most of the time for transcription of eukaryotic genes
mediator complex
mediator complex bridges ___ and ___
RNA pol II and enhancer
activators are responsible for much of the ___ in levels of transcription of different genes
variation
activators stimulate recruitment of ___ and ___ to promoters
basal factors and RNA pol II
activators recruit ___ to open chromatin structure
coactivators
activator proteins have at least ___ functional domains
two
most DNA binding proteins are dimers
true/false
true
domain that binds to a specific enhancer
DNA binding domain
domain that binds to other proteins
activation domain
domain that allows an activator to interact with other proteins
dimerization domain
two domains that every activator has
DNA binding domain
activation domain
two examples of a DNA binding domain
- helix-turn-helix
- zinc finger
DNA binding domains fit within the ___ of DNA
major groove
dimerization domains are specialized for ___ interactions
polypeptide-polypeptide
multimeric proteins made of identical subunits
homodimers