epigenetics

Question 1

effects of paternal grandparent diet on children

Answer 1

poor diet decreased mortality rate

Question 2

Genetically comparable mothers who were fed slightly different diet (low or high “methyl donor” ingredients) during gestation and nursing produced very different offspring

Answer 2

The AGOUTI gene is turned off in the darker, smaller mouse. Agouti protein regulates both coat color and feeding habits.
Methyl donor ingredients:
folic acid, vitamin B12, choline, betaine
High MD mother: skinny
Low MD mother: Fat

Question 3

epigenetic changes lead to

Answer 3

diversity of cell types

Question 4

Epigenetic Characteristics: A Definition:

Answer 4

1) Different gene expression pattern/phenotype, identical genome
2) Inheritance through cell division, even through generations
3) like a switch: on/off
4) erase-abe (interconvertibel) THERAPEUTIC POTENTIAL

Question 5

flipping switches as a visualization of

Answer 5

epigenetic gene expression pattern

Question 6

differentiated cell has lights

Answer 6

partially on

Question 7

induced pluriotpoten stem cell has lights

Answer 7

all turned on

Question 8

Why is erasure and resetting of methylation patterns of imprinted genes during gametogenesis esstenial?

Answer 8

imprinting! so not all male gametes have the same expression, nor do female gametes, so you turn them all on then silence so that no matter the combination, it works

Question 9

proper imprinting

Answer 9

1. meiosis
2. erasure: DNA de-methylation
3. Sex-specific gene silencing: DNA methylation
4. fertilization

Question 10

DNA methyltion locks in the

Answer 10

repressed state

Question 11

DNA methylation occurs only on

Answer 11

cytosines of CpG

Question 12

DNA methylation does not affect the

Answer 12

base paining of 5-meC with G

Question 13

DNA methylation contributes to

Answer 13

gene silencing by solidifying the repressed state. It uses a cofactor to do this. The cofactor makes this work at a higher capacity

Question 14

Maintenance methytransferase propagates

Answer 14

epigenetic marks throughout somatic cell division

new strands lack the methyl group, so this recognizes and methylates the new strands

Question 15

histone H3 modifications

Answer 15

affect gene expression
the repressive histone mar can be off: with no Ac
Or ON, which Ac on the DNA

Question 16

Problem for maintaining an epigenetic state (DNA methylation or histone mod.):

Answer 16

• DNA is half old/half new

- Histones are half old/half new

Question 17

examples of epigenetic phenomena:

Answer 17

1. chromatin-mediated gene silencing
2. centromere marking by histone variant CENP-A
3. Prions
4. Reinforceing feedback loops involving trans-acting factors that have a specific initiation event and are “inherited” in cytosol during cell division

Question 18

Reinforceing feedback loops involving trans-acting factors that have a specific initiation event and are “inherited” in cytosol during cell division

Answer 18

1. bacteriophage lambda repressor mechanism

2. feedback loops in the initiation of certain cancers that operate through cytosolic signaling proteins and miRNA

Question 19

chromatin-mediated gene silencing

Answer 19

heterochromatin domains
X-inactivation
imprinting

Question 20

cytosolic epigenetic inheritance in cancer is an example of

Answer 20

non-nuclear epigenetics

Question 21

silencing of tumor suppressor gene (TSG) by

Answer 21

5meC can lead to cancer

Question 22

correcting epigenetic patterns as a cancer therapy

Answer 22

prevetning inheritance of aberrant gene silencing
DNA methyltrasnferase and HDAC inhibition can inhibit tumor genes
interconveratable states, can drug a system to reset cells to a normal state and reset homeostasis

Question 23

3 chemical modifications to DNA

Answer 23

1. methylation (imprinting)
2. heterochromatin domains (HATs an HDAC)
3. x inactivation

Question 24

diseases of epigenetic phenomena

Answer 24

1. angelman

2. prader wili