Chapter Twenty: Epigenetics Flashcards

1
Q

three techniques to monitor regulation of gene expression

A
  1. northern
  2. microarray
  3. RT-PCR
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

techniques to monitor gene expression depend on ___

A

hybridization

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

heritable alterations in gene expression that do not involve a mutation or change in base pairing

A

epigenetics

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

the DNA sequence in genes is not the only carrier of ___

A

genetic information

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

write the definition of epigenetics

A

heritable self-perpetuating changes in gene expression not caused by base pair sequence changes

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

epigenetics usually involves modified ___, ___, or ___

A

cytosine residues, histone tails, or small RNAs

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

epigenetic factors determine whether a gene is ___ or ___

A

on or off (expressed or not)

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

phenomenon in which expression of an allele depends on the parent that transmits it

A

genomic imprinting

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

about ___ imprinted genes have been identified

A

100

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

paternal allele is not transcribed

A

paternally imprinted

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

maternal allele is not transcribed

A

maternally imprinted

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

imprinted means ___

A

silenced

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

a methyl group is added to the cytosine base in a 5’ CpG 3’ dinucleotide by DNA methyltransferase

A

DNA methylation

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

regions with a high concentration of CpG dinucleotides

A

CpG islands

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

CpG islands are usually ___ and located near a ___

A

unmethylated
promoter

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

an ___ binds to unmethylated CpG islands, the chromatin is ___ and transcription is ___

A

activator
open
activated

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

DNA methylation at CpG islands ___ gene expression

A

silences

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

repressors called ___ bind to methylated CpG islands and close the chromatin structure

A

methyl-CpG-binding proteins (meCPs)

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

cytosine methylation pattern is ___ during DNA replication, so DNA methylation is ___ throughout cell division

A

copied
maintained

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

special ___ at the replication fork methylates the newly synthesized DNA strand

A

DNMT

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

sex-specific DNA methylation mediates ___

A

imprinting

22
Q

imprinting occurs through these two mechanisms

A
  1. insulator mechanism
  2. ncRNA mechanism
23
Q

epigenetic imprints remain throughout the ___ of an animal

24
Q

in germ cells, epigenetic imprints ___ each generation

25
during meiosis, imprints are ___ and new ones are set based on the ___ of the organism
erased sex
26
human ___ show imprinting
pedigrees
27
___ syndrome occurs when a deletion in chromosome 15 comes from the father, ___ syndrome occurs when it is inherited from the mother
prader-wili angelmans
28
imprinting only occurs in ___
placental mammals
29
most imprinted genes control ___
prenatal growth
30
imprinting is ___ (100 genes identified so far)
rare
31
all cells in multicellular organisms have the same ___
genes
32
cell types are different because of ___ differences
gene expression
33
determines gene expression and potential fates of a cell, often a transcription factor
master regulator
34
cells "remember" their fate from cell generation to generation partly because histone modifications that repress transcription at master regulatory genes are ___
copied at the replication fork
35
drosophila Cox (homebox) genes encode transcription factors that set up animals ___
segmented body plan
36
highly compacted chromatin found in all cells
constitutive heterochromatin
37
constitutive heterochromatin is found at ___, which are enriched in ___; important to prevent ___
centromeres transposable elements TE mobilization
38
constitutive heterochromatin is also found at ___
telomeres
39
___ transcribed from centromeres initiates heterochromatin formation
ncRNA
40
ncRNA is converted to ___ which binds to ___
siRNA argonaute (ago)
41
ago recruits ___ that results in heterochromatin formation
histone methyltransferases
42
plant heterochromatin is ___ after cell division
reformed
43
which base gets methylated in epigenetic control
cytosine
44
mammalian cells ___ which X chromosome was inactivated
remember
45
when an environmentally induced trait (not caused by a base pair mutation) appears in an individual's descendants whose DNA was not directly exposed to the environmental trigger
transgenerational epigenetic inheritance
46
methylation marks are released during meiosis in ___ but not ___
animals plants
47
piRNAs transmit memories of ___
TE invasion
48
organisms try to ___ TE mobilization to prevent mutations or chromosomal rearrangements
limit
49
why can TEs move with a minimal effect on phenotype in humans?
only 1% of the human genome codes for proteins that affect phenotype
50
environmentally induced trait that is displayed only in the child, or child and grandchild of an originally exposed female, or child of an exposed male
intergenerational epigenetic inheritance