Intro to Epigenetics Flashcards Preview

Developmental Genetics > Intro to Epigenetics > Flashcards

Flashcards in Intro to Epigenetics Deck (43):
1

Define Epigenetics.

A change in phenotype that is caused by non-DNA sequence changes inherited through mitosis.
- Identical sequences.

2

What three components of epigenetic mechanisms?

- Histone tail modifications.
- DNA cytosine methylation.
- Non-coding RNAs.

3

When can you modify histone tails?

.

4

What is the result of DNA methylation (5meC)?

.

5

Adenine methylation is involved in..?

.

6

What are three types of non-coding RNAs involved in epigenetic modifcations?

.

7

How much of RNA will give rise to a protein?

0.1%, (99% won't give rise to protein).

8

RNA regulation involves?

.

9

What experiment won the nobel prize in 2006, in relation to the RNA world?

.

10

What other experiments contributed to the field of RNA?

.

11

Describe the miRNA and siRNA silencing pathways.
Draw the diagram.

.

12

What are the two outcomes of miRNA and siRNA silencing pathways?

- mRNA cleavage and translation repression.

13

Where are miRNA genes often located?

.

14

What is heterochromatic silencing?

- Silencing of tightly packed DNA.
- Down-regulation to prevent insertion into lncRNAs?

15

How much of the genome is transposons and retrotransposons?

.

16

Describe the process of transacting siRNA silencing?

.

17

What is the difference between the one hit and two hit pathways?

.

18

What is the role of TAS3 in tasiRNAs?

.

19

What is the effect of the rdr6 mutation leading to no production of tasiRNAs in ARF3 and ARF4?

.

20

Describe the process of miRNA processing.

.

21

What are the functional domains of the Argonaute protein? Draw.

.

22

How was the Ago structure determined?

.

23

PIWI is the ______ domain.

Cleavage.

24

What are the small RNA classes in plants, their precursors and quantity?

.

25

What are the RNA silencing components, their function and organism?

.

26

What are the roles of silencing in nature?

.

27

What are some targets of some conserved miRNAs and their functions?

.

28

What is an example of RNA viruses being targeted by RNA silencing?

.

29

What is the function of PAZ domain in the Ago protein?

.

30

How is adaptive immunity passed through the plant?

.

31

What happens if transposon activity is not controlled (silenced)?

.

32

What are the methods for silencing transposon activity?

DNA methylation, histone modification and siRNA production.

33

How much of our genome is derived from transposons?

44%

34

Where are heterochromatic siRNAs preferentially derived from? Why?

Pericentromeric regions and centromeric regions.
Density of sRNA-homologous loci is highest in centromeric and pericentromeric regions, which contain lots of repeat sequences like transposons.

35

siRNA direct transcriptional silencing.

.

36

In terms of chromatin regulation, how can you turn a gene off?

.

37

Describe the structure of histones.

.

38

Describe the histone code hypothesis.

.

39

Summarise the RdDM Pathway.
(RNA derived DNA methylation).

.

40

Methylated transposable elements can silence their flanking gene.

True or False?

True.

41

What is the effect of reduced cytosine methylation in transposable elements?

.

42

What is the effect of transposons jumping next to genes?

.

43

How can RNAi tech be used to identify gene function?

.