Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

BMS > Transcription, RNA Processing (Hampsey) > Flashcards

Transcription, RNA Processing (Hampsey) Flashcards

(54 cards)

Start Studying
1
Q

Rifampin in binds to

A

Bacterial RNAP

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

Prokaryotic RNAP consists of

A

Sigma subunit, associates with core enzyme (alpha, alpha, beta, beta, omega) to generate hold enzyme

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

What happens during prokaryotic transcription

1. Initiation

A

Holo-RNAP (sigma) binds promoter, principal site for regulation of transcription

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

What happens during prokaryotic transcription: Elongation

A

RNAP “leaves the station”; sigma dissociates from RNAP & promoter

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

What happens during prokaryotic transcription: Termination

A

DNA-RNA-RNAP complex disassembles..dependent on specific signals (Rho dependent or Rho independent)

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

Structure of a bacterial promoter, how many sigma binding sites?

A

2
-35 sequence (TTGACA)
Pribnow box (TATAAT)

**these consensus sequences are not exact, don’t want overly tight binding

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

Rho-dependent transcription termination

A

Travels along nascent mRNA, comes in contact with RNAP and dissociates complex to stop termination

*torpedo, ATP dependent

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

Rho-independent transcription termination

A
  • Stem and loop
  • mRNA folds up and makes this stem
  • still within RNAP and complex disassociates
  • 3’ end: UUUU-OH
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

True or false: there are DNA sequences that tell transcription to stop

A

TRUE…..Rho-dependent/independent transcription signals are encoded for by DNA

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

2 notable features of eukaryotic transcription

A

1) 5’-CAP

2) 3’ polyA tail

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

Alpha-amantin

A
  • eukaryotic transcription inhibitor

- binds RNAP III and inhibits elongation (just like rifampicin does this in bacteria)

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

DNA –> rRNA via

A

RNAP I

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

DNA–> mRNA via

A

RNAP II

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

DNA–>tRNA/ssRNA via

A

RNAP III

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

MRNA—>Protein via

A

Ribosome

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

These bind to regulatory proteins and activate stuff…
>250bp
-dsDNA, function in any direction, and are binding sites for transcription activators

A

Enhancers

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

CpG islands make up

A

Proximal promoter
-bind regulatory proteins for housekeeping genes & certain activator proteins
Ex: Sp1: most well characterized activator for proximal promoter

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

Core promoter is the

A

TATA box
-40 to +40
Transcription start site +1 (INR, DPE is +20)
Binding site for RNAP II and GTFs

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

What makes up core promoter

A

BRE (TFIIB recognition element) @ -35
TATA @ -25INR +1
DPE +30

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

Proximal promoter and Core promoter….

A

Span ~80 bp & flank start of transcription

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

What binds to dsDNA Pre initiation complex

A

GTFs
—>leads assembly of RNAP II
Recognize specific stuff in promoter, similar to sigma in bacteria

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

What positions RNAP II at the promoter

Study These Flashcards
A

GTFs (they recognize promoter elements)

23
Q

GTFs specific to RNAPII

Study These Flashcards
A

TFIIA, TFIIB, TFIID

24
Q

TFII B binds to

Study These Flashcards
A

BRE of core promoter

25
TFII D binds to
Promoter - includes TBP (TATA binding protein) + 14 TBP associated factors (TAFs) - nucleases assembly of transcription Pre initiation complex >>>>TBP (part of TFDII) binds TATA > bend in promoter DNA> allows TFBII and other to bind>>>>TFIIE,TFIIH bind subsequently, involved in promoter melting so RNAP II transcription can begin
26
Which GTF is the last to bind?
TFII H | -has helicase activity and can unwind DNA, then DNA can descend into active site of RNAPII
27
TFIIH implicated in
XP (xeroderma pigmentosum) TTD (trichotriodystrophy) Cockade syndrome (CS)
28
Many activators can stimulate transcription by binding GTFs in order to
Recruit or stabilize their binding to core promoter
29
Where is the only place where 5' to 5' linkage occurs
7-methylguanosine cap at 5' ends of mRNAs - via triphosphate linkage - as soon as mRNA emerges from RNAP it's capped 4 protection
30
What occurs during polyadenylation of a primary transcript
There is a cleavage signal: AAUAA, and 2 enzymatic reactions 1) cleavage by specific endnonuclease 2) addition of tail by polyApolymerase (not encoded in DNA, uses ATP)
31
Why is polyadenylation of a primary transcript needed?
For mRNA stabilization, transport of mRNA from nucleus to cytoplasm -uses ATP
32
Direction of flow of genetic information
5' to 3'
33
What's the organization of a human B-glob in gene?
3 exonuclease, 2 introns | -before RNA translated, splicing occurs
34
How is b-glob in gene processed?
Bglobin gene-[transcription, 5' cap, poly a tail]->primary transcript (with introns)-[splicing]->B globin mRNA
35
5' splice site of upstream exon
AG|GUAAGU First exon always begins with a GU
36
3' splice site of downstream exon
CAG|G ***exon always ends with AG
37
Exon begins/ends with
GU.......AG
38
Where is there the only 2' to 5' PD bond?
Lariat intermediate (which eventually becomes intron)
39
Transesterification reaction
1) cleave PH bond btwn exon 1, intron 1 (2'OH branch site of intron) ---->form the 2'-5' PD bond 2) 3'-OH of exon 1 cleaves PD bond btwn intron, exon 2 - -->exon 1 joined to exon 2, intron released as lariat
40
Spliceosome assembly is de novo from _____
SNURPs
41
SNURPs recognize
5' splice site (AG|GU) U1 Branch sit 3' splice site(AG|G) Branch site U2 +U4U5U6 complex -->basically scrunched it up
42
Spliceosome assembly requires
ATP
43
B-thalassemia is an intron mutation..what kind?
``` Point mutation (substitution) -now machinery thinks this is splice site and have 6 extra amino acids as a consequence ```
44
Tamoxifen
- antagonist - binds to estrogen receptor as a competitive inhibitor - fails to induce conformational change required for transcription activation
45
How do steroid hormones work?
Directly stimulate transcription as hormone-receptor complexes...receptors are transcription factors; bind to dsDNA (promoter) and can cause conformational changes DNA-Hormone-Receptor Comoplex interacts with coactivator complex --> RNAP II transcriptional machinery stimulated
46
Steroid hormones bind ____ and recruit chromatin remodeling proteins
Enhancer sequences
47
How do coactivators work?
Recruit/stabilize RNAP II/GTF to core promoter -clear a path for RNAP II by altering chromatin DNA template By remodeling chromatin, can now recruit coactivator complex (how estrogen works)
48
What do histone acetyltransferases (HATs) do?
Acetylation of histone lysine residue in N-terminal tails of H3, H4 -->chromatin modification *reversible by histone deactylases (HDACs)
49
ATP-dependent remodeling complexes (aka remodeling engine) does what?
Remodel nucleosomes via ATP hydrolysis | --> TFs bind to DNA and promote gene transcription
50
Mechanism of glucocorticoid receptor
Cortisol binds -> conformational Chang win receptor -> zinc finger binding domain uncovered -> steroid receptor complex interacts with specific regulatory DNA sequences (GRE) -hormone receptor complex (w/ coactivator proteins) controls transcription of targeted genes
51
MMTV (mouse mammaery tumors virus)
-DNA virus - breach cell carcinoma - MMTV has DNA sequence identical to estrogen enhancer, integrates next to Wnt-1-protooncogene so WNt1 now regulator of cell proliferation under control of estrogen
52
TFIIH
Couples transcription with DNA damage repair Issue with TFII H associated with some is eases (XP,TTD,CS) since DNA rapier altered
53
Alpha amantin
Binds to RNAP II , inhibits elongation of transcription
54
Rifampicin
Antibiotic,binds to RNAP of bacteria

BMS (7 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions