Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Control Of Gene Expression > Regulation Of Transcription 2 > Flashcards

Regulation Of Transcription 2 Flashcards

1
Q

What is rna editing

A

Alteration or modification of nucleotides in rna

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

What rna goes through editing

A

Mrna tRNA and rRNA

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

Which disease is caused by editing

A

Atherosclerosis

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

How can editing affect the brain

A

High functioning things like depression

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

How does editing allow parasites to be drug targets

A

Via U insertion in their mt

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

Give 2 examples of methylation editing

A

M5cytosine - cytosine at n 5 is methylated irreversibly

M6adenine - methylated at 6’

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

How does editing affect action of uridine which binds to adenine

A

It is converted to pseudouridine via an isomerisation reaction

Produces an extra H bond

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

What is better about pseudouridine edited from uridine

A

It has extra h bond potential which increases rna stability

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

Bases can be fully changed in identity aswell as altered. What are the 2 ways

A

A deamination to I (inosine)(recognised as G)

C to U deamination (loss of NH2)

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

How can U insertion or U from c deamination affect mrna

A

Can cause introduction of a start AUG codon or a stop UAA/UAG codon

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

How does editing such as change in bases affect splicing

A

Can change splice sites

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

Can editing cause change in AA sequence

A

Yes Eg via insertion/deletion or alteration via deamination

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

Does M6A methylation affect base pairing of A with U

A

No

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

How can m6a affect rna

A

Methylation can either stimulate protein binding. Proteins which improve rna stability

Or

It can block then causing instability and degradation

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

Which eraser of the m6a is involved in obesity

A

FTP

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

Other than protein binding what does m6a affect

A

Splicing, export and translation

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

How does cytidine deamination to U affect apo B gene in intestines

A

In intestines the c is deaminated to U in the apoB gene introducing a new stop codon. The protein is much shorter forming apob48 and without an LDL receptor

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

Does cytidine deamination into U occur in liver apoB gene

A

No. There is no stop codon and so long protein apoB 100 is produced with an LDL receptor intact

19
Q

Which enzyme deaminates A to I

A

Adar 2

20
Q

How has A deamination to I via adar 2 affected transmission of glutamate Nt across synapse

A

Changed amino acid in transporter from Q glutamine to R arginine. This transporter is now not permeable to calcium = no transmission

21
Q

How is ribose modified in trna, snrna and rRNA

A

2’ O methylation of ribose

22
Q

How does ribose 2’ o methylation affect things in trna rRNA and snrna

A

Changes stability by blocking nucleases

Also changes protein binding

23
Q

What happens to yeast if there’s no rRNA 2’ o methylation on ribose

A

They die

24
Q

What Happens to yeast if the pseudouridine from isomerisation of uridine in rRNA is removed

A

Defect in translation as it needs rRNA stability

25
Q

Which enzyme is mutated which modifies rRNA in dyskeratosis congenita

A

Pseudouridine synthase

26
Q

Does editing also occur on non coding rna

A

Yes Eg sn rna 2’ o methylation

27
Q

Explain the structure of nuclear pores

A

Nucleoplasm and cytoplasm are separated by the outer and inner nuclear membrane

There is a nuclear basket and on the cytoplasmic side there are long cytoplasmic filaments

28
Q

What 2 things are needed for exportation

A

Export factors and export adapters

29
Q

What do export adapters do

A

Couple processes like capping, poly A which have export factors with mrna to export receptors/factors

30
Q

What is an important thing in exportation for energy

A

Ran gtp

31
Q

Which export factors carries trna

A

Exp-t

32
Q

Which export factor carries mirna

A

Exp-5

33
Q

Which rnas need export adapters to attach to them and connect them to export receptors

A

Snrna,mrna and rRNA

34
Q

Which export adapter is the main one in mrna exportation

A

ALY/yra1

35
Q

What are the 2 human export factors for mrna (attach to ALY/yra1)

A

TAP and p15

36
Q

What is rna localisation described as

A

Asymmetric

37
Q

What is importance of rna localisation being asymmetrical

A

Localised protein synthesis
Generates cell polarity in development
Prevents expression of genes I. Wrong place

38
Q

Give an example of cell polarity via asymmetrical mrna localisation

A

Bcd bicoid mrna localised on edge of oocyte to form the APVD axis

When proteins are translated they form a gradient forming the axis

39
Q

Give an example of localised translation of mrna = prevents expression In wrong place

A

NTs mrna is translated at the synapse after travelling down dendrites

40
Q

Which 2 modes of transport do mrna localise through

A

Diffusion and active transport

41
Q

Which proteins hold and localise mrna after diffusion localisation

A

Anchor proteins

42
Q

Give an example of active transport localisation

A

Mrna moves down dendrite via AT anchored to the cytoskeleton

43
Q

What state is mrna in until right localisation

A

Inactive state so no translation occurs

Control Of Gene Expression (13 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions