Brainscape's Knowledge GenomeTM

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


See full index

Regualtion Of Gene Expression > Lec1/2: Transcriptional Control > Flashcards

Lec1/2: Transcriptional Control Flashcards

1
Q

what is RNA pol 1 used for?

A

Ribosomal RNA genes

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

What is RNA pol 2 used for?

A

Protein coding genes, miRNAs and non-coding RNAs

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

What is RNA pol 3 used for?

A

tRNAs

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

Where is an enhancer located?

A

-1000bp

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

Where are Upstream Sequence elements (USE) located?

A

-100bp

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

Where is TATA box located?

A

-30bp (-28,-32)

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

Where are initiator elements located?

A

+1bp

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

What are initiator elements?

A

Adenine base flanked by pyrimidine sequence. (YYANYAYY)

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

What happens at the TATA box?

A

Where RNA pol 2 interacts but through proteins not directly

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

How is an initiator complex assembled?

A

-TF2D binds TATA box (90 degree angle in DNA
-TF2D bound by TF2A
-TF2B also binds TF2D
-RNA pol 2 recruited and comes with TF2F attached
-TF2E and TF2H bind as well

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

What is TF2D?

A

TATA binding protein (TBP)

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

What is TF2A function?

A

Stabilises TF2D and DNA interaction

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

What is TF2B function?

A

To recruit RNA pol2

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

What is TF2E function?

A

Functions as an ATPase to supply energy

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

What is TF2H function?

A

Helicase

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

What is TF2F function?

A

Comes prebound to RNA pol2

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

What is the pre-initiaton-complex (PIC) made up from?

A

TF2A,B,D,E,F,H and RNA pol2

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

What is difference with TATA less promoters?

A

They have DPE (downstream promoter elements) instead of TATA box but also still has initiator sequence

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

What is DPE downstream promoter elements sequence and where is it located?

A

AGAC (+28-+32)

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

What Transcription factor changes in TATA less promotion?

A

They use TF2I instead of TF2D

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

What is focused transcription initiation?

A

Focused is usually highly conserved genes that have a TATA box

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

What is dispersed transcription initiaton?

A

Dispersed usually has DPE (downstream promoter elements) and are constitutively conserved.

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

What are the two types of transcription iniitiation?

A

Dispersed and focused

24
Q

What has a large effect on the level of transcriptional control?

A

Transcription factors that bind upstream of TATA/INR

25
Q

What types of TFs are there?

A

-confer general transcription
-confer tissue specific transcription
-confer inducible transcription

26
Q

Example of TFs that confer general transcription?

A

SP1

27
Q

Example of TFs that confer tissue specific transcription?

A

MyoD and Oct-2

28
Q

Example of TFs that confer inducible transcription?

A

CREB and Esteogen receptor

29
Q

What are enhancers?

A

Where TFs bind to. activate transcription can be placed 1000sbp away its orientation doesn’t matter and can be up or downstream

30
Q

How do enhancers work?

A

They form a loop brining the Transcription factor to the pre-initiation complex.

31
Q

What are silencers?

A

Area of genetic code that Can act 1000s if base pairs away and loop to Pre-initiation complex but repress expression all control.

32
Q

What are insulators?

A

Molecules that control the activity of enhancers and silencers

33
Q

How do insulators control expression?

A

By blocking interaction between enhancers,silencers and PIC

34
Q

Where are insulators located?

A

Between enhancers/silencers and their promoters

35
Q

Where are insulators found?

A

Between silencer/enhancers and promoters

36
Q

What makes up LCR?

A

Made of enhancers and silencers and promoters

37
Q

What is the LCR?

A

Locus control region

38
Q

What does TAD stand for?

A

Topologically associated domain

39
Q

What are TADs?

A

Large multi component domains that facilitate long range interactions. Allow for control of gene expression by restricting chromatin reactions

40
Q

What does LADs stand for?

A

Lamellar associated domain

41
Q

What are LADs?

A

Areas of DNA consisting of transcription ally silent chromatin enriched with lys27 on histone H3

42
Q

What happens to if TADs are disrupted?

A

Result in altered gene expression and can cause genetic disease or cancer.

43
Q

What’s the structure of a TF?

A

A modular structure

44
Q

What is a modular structure?

A

This means all AAs involved in binding are in one place.

45
Q

What is a homeodomain?

A

-transcription factor binding domain

-60 residue, 3 helix domain. Helices 2 and 3 form helix-turn motif.

46
Q

What are zinc fingers?

A

-transcription factor binding domain

-motif that uses 2x cystine and 2x histidine to hold the zinc forming finger like domain

47
Q

Where do you u find homeodomains?

A

Tend to be found in development control genes for example HOX genes

48
Q

Where do you find zinc finger domains?

A

Found in the major groove of DNA, usually used by steroid hormone receptors to bind DNA.

49
Q

Give an example of basic binding domain?

A

Leucine zipper

50
Q

What are leucine zippers?

A

-transcription factor binding domain
-basic basic being domains
-alpha helix with leucine residue every 7 residues

51
Q

What’s the structure of leucine zippers?

A

-They are dimers
-3 types of monomers allowing for 6 different dimer combinations

52
Q

What are activation domains?

A

Domains that bind and work through interaction with the PIC.
Can work through mediators after PIC binding

53
Q

What are the 3 methods of inhibitory transcription domains?

A

-competition
-quenching
-recruitment of co-repressors

54
Q

How do competitive TFs work?

A

Through competition of repressor and activator proteins

55
Q

How does quenching inhibition work?

A

Type 1: repressor binds and blocks DNA binding region of an activator
Type2: Repressor binds to and blocks activation domain of an activator

56
Q

Examples of co-repressors inhibitory TFs recruit?

A

Mad recruits NCoR + Sin3A

57
Q

Wha ya the key role of TFs?

A

-Regulate differentiation and tissue specific gene expression
-for example MyoD in muscle cells

Regualtion Of Gene Expression (2 decks)

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