Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

BIO 142 > Gene Regulation in Eukaryotes > Flashcards

Gene Regulation in Eukaryotes Flashcards

(61 cards)

Start Studying
1
Q

the most rapid form of regulation of the amount of protein

A

the degradation of proteins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

what is used by eukaryotes that is not used by prokaryotes in gene regulation?

A

RNA splicing and chromatin remodeling

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

what does RNA splicing allow?

A

different traits to be produced from the same gene due to the sequence that it is stitched in

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

HDACs

A

histone deacetylases

remove acetyl groups

example of negative control because they re-condense chromatin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

HACs

A

histone acetylases

add acetyl groups

example of positive control because they decondense chromatin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

how do acetyl groups de-condense chromatin?

A

they neutralize the positive charge on lysine residues which makes less force of attraction between the negatively charged DNA and the lysine. opens up.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

DNA methylation

A

negative control

the added methyl groups allow proteins to bind to the DNA that condenses it

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

why do histones bind tightly to DNA?

A

histones are positively charged and DNA is negatively charged

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

differential gene expression

A

responsible for creating different cell and tissue types

all cells have the same genes but express them differently

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

3 steps to regulate gene expression within the nucleus

A
  1. Chromatin remodeling (degree of which chromatin is coiled)
  2. Transcriptional regulation
  3. Alternative splicing
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Stain and chromatin

A

areas that are unwound will stain lightly. indicates they will be expressed at high levels. (euchromatin)

areas that are wound will stain dark, indicates they will be expressed at low levels (heterochromatin)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

x chromosomes and DNA methylation

A

since females have 2 X chromosomes, one is condensed by DNA methylation

random which of the chromosomes will be affected. means that on an organismal level there will be a 1:1 ratio of alleles present overall.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Barr body

A

stain that is produced by X chromosome that is wound by DNA methylation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Mosaicism

A

different cells exhibit different traits

occurs when female is heterozygous for X-linked trait

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

example of mosaicism

A

tortoise shelled female cats (heterozygotes)

some cells exhibit the black allele, while others exhibit the orange all due to random condensation of X-chromosome

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

can male cats be tortoise shelled?

A

yes

nondisjunction (failure to separate normally) can occur and XXY male can have mosacism

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

DNA methyltransferases

A

add methyl groups to chromatin

results in condensed chromosomes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Nucleosomes

A

repeating bead-like structures that consist of DNA wrapped around histones

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

DNAase treatment

A

tests for open chromatin because it only degrades open chromatin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

H1 protein

A

maintains the structure of each nucleosome

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

30-nanometer structure

A

H1 proteins interact to form a tightly wound fiber

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Acetylation

A

Acetyl groups neutralize the positive charge on lysine and loosen the interaction between positively charged histones and negatively charged DNA

this loosens the chromatin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Histone acetyl transferases

A

put acetyl groups on DNA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Histone deacetylases

A

remove acetyl groups on DNA

DNA tightens

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Epigenetic inheritance
inheritance not due to differences in gene sequences
26
What is an example of epigenetic inheritance?
inheritance not due to differences in gene sequences
27
What do all eukaryotic genes have?
a common promoter
28
TATA binding protein
binds eukaryotic promoters to the TATA box
29
Where is the promoter found?
at the beginning of
30
TATA box
sequence of DNA that is at the core of the promoter where the TATA binding protein binds
31
Promoter proximal elements
DNA regions upstream of the promoter that are UNIQUE to specific genes
32
Enhancers
located far away from the promoter either upstream (5') or downstream (3') different enhancers are associated with different genes
33
Activator proteins
bind to enhancers and stimulate the transcription complex
34
Silencers
similar to enhancers but repress gene expression
35
Classes of proteins that bind to the regulatory sequences of eukaryotic genes
Basal transcription factors Regulatory transcription factors
36
Basal transcription factors
do not regulate transcription, but are required to start transcription they are general
37
example of a basal transcription factor
TFIID protein that binds directly to TATA box
38
regulatory transcription factors
bind to enhacers, silencers, and promoter-proximal elements responsible for the expression of particular genes in particular cell types at certain stages of development unique to particular genes
39
How are regulatory transcription factors triggered?
extracellular signals can trigger them
40
What can regulatory transcription factors do?
they can get histone acetylation to occur and certain genes to be expressed can recruit the basal transcription complex to bind to a specific promoter
41
What completes the basal transcription complex?
RNA polymerase II
42
What happens when chromatin decompresses?
the promoter is exposed
43
How can enhancers control genes far away?
DNA looping
44
Alternative splicing
removes introns and splices exons together allows one gene to code for many different things
45
snRNPs
bind to consensus sequence at the 5' exon-intron boundary. another snp binds to 3' boundary. together they physically loop the introns
46
Spliceosome
complex that cuts the RNA, releases introns, and joins exons
47
Example of how alternative splicing can promote diversity
the gene for the muscle protein tropomyosin is spliced in five different ways for different tissue types
48
what percent of genes have alternate splicing?
90% technically humans have less genes than wheat
49
RNA interference (RNAi)
can result in rapid degradation of mRNA in the cytoplasm targets specific mRNAs based on single-stranded microRNAs
50
microRNAs
transcribed in the nucleus, but are not translated bind to RNA-induced Splicing Complex where they become single stranded then, single stranded microRNAs can bind to mRNA with help of RISC
51
RISC
binds microRNAs to mRNA enzyme inside RISC cuts the mRNA to degrade it
52
Protein kinase rapamycin (mTR)
phosphorylates translation initiation factors these factors recruit the ribosome under stressful conditions, protein kinase rapamycin activity is blocked this prevents most translation general form of regulation
53
3 examples of post translational control
1. localization 2. modifications 3. degradation
54
Localization
post-translational control proteins can have a signal sequence to quickly change their cellular location
55
Ex of localization
transcription factors are sequestered in the cytosol until given a signal to move to nucleus common mechanism for hormone receptors
56
Modification
post-translational control Covalent modifications to proteins (like the addition of a phosphate group) can be used to quickly change the 3D shape and function of a protein
57
Ex of modification
CDKs add phosphate groups to target proteins to begin mitosis
58
Degradation
post-translational control regulating the lifetime of a protein is a way to control its actions
59
Proteasomes
control random degradation of proteins by preventing hydrolytic enzymes from floating around cytoplasm and degradating proteins
60
Ubiquitin
polypeptide that is often linked to proteins designated for degradation this ubiquitin-protein complex then binds to a complex called a proteasome
61
What happens once ubiquitin-protein complex binds to the proteasome?
Protein is cleaved from ubiquitin and proteases digest the protein

BIO 142 (14 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions