Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

3207 > 20 > Flashcards

20 Flashcards

(56 cards)

Start Studying
1
Q

recoding

A

stop codons being used for other functions

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

ribosome rescue

A

occurs when there is no stop codon to trigger termination

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

stop codon recognition in bacteria

A

RF1 and RF2

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

stop codon recognition in eukaryotes

A

eRF1 and eRF3

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

what tRNAs recognize stop codons

A

none

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

what recognizes stop codons

A

class 1 release factors

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

what are the class 1 release factors

A

eRF1 euk
RF1 and RF2 in bacteria

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

how many class 1 release factors in euk and in batceria

A

euk- one
bact- two

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

relation of class i release factors in bacteria and euk

A

not related but structually similar sequence of

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

class i release factors

A

GGQ with the second glutamine methylated GGmeQ

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

molecular mimicks of tRNA

A

class 1 release factors

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

what undergoes confromational changes when release factors bind

A

G530 and A1492 in the decoding centre

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

what happnes in the peptidyl transferase centre when class 1 release factors bind

A

the 2’OH on the peptidyl tRNA is important for hydrolysis reaction

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

how do release fcators in bacteria reach the ribosome

A

RF1 and RF2 enter the A site on their own and bring about peptide hydrolysis

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

how do RF1 AND RF2 bind in bacteria

A

recognize stop codons

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

RF1 stop codons

A

UAA
UAG

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

RF2 stop codon

A

UAA and UGA

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

what release factor is a GTPase

A

RF3

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

what does RF3 do

A

promotes the dissociation of RF1 and RF2
mostly significant when supply of RF1 and RF2 is limiting

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

what is RF3 related to

A

EFG

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

what is related in the case of mimatched complexes in the P site

A

RF3

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

what reaction happens in the RRF

A

translocation type of step

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

what does the transloaction step lead to

Study These Flashcards
A

dissasembly of the ribosome in the RRF with EFG

24
Q

what happens when a translocation type of step occurs in the RRF with EFG promotes dissasembly ofthe ribosome

25
what are some molecular mimmicks of tRNA
RRF EFTu EFG
26
how do release factors reach the ribosome in euk
eRF3 brings eRF1 into the A site of ribosome
27
what is eRF3 equivalent to
EFTu
28
what binds to the A site
eRF1/eERF3GTP
29
what recognizes the stop coodn
eRF1
30
steps of stop codon recognition in euk
eRF1 undergoes a conformational change GTP hydrolyzed by eRF3 eRF1 accomodates into the peptidyl transferase centre inducing peptide release eRF1 adn eRF3GDP remain associated with post termination complexes
31
what are the two steps of ribosome recycling
dissociation o the 60s subunit dissociation of the 40s subunit fron the deacylated tRNA and mRNA
32
what can erros in the ribosome recylcing lead to
accumulation of ribosomes at stop codons triggering long qeues of ribosomes to form immediately upstream or translation of downstream open reading frames by reinititaion of unrecycled ribosomes downsteram of the stop coodn
33
what does accumulation of riboosomes around the stop codon lead to
reduces number of ribosomes available to initiate new founds of translation of other mRNAs affecting the proteome
34
loss of 60s recycling leads to
puaidng of 80s ribosome at stop coodns upstream ribosomes collide wiht this and push it into the 3'UTR leading to reinitation of tranlastion and translation of unintended ribosomes
35
loss of 60s recycling leads to
puaidng of 80s ribosome at stop coodns upstream ribosomes collide wiht this and push it into the 3'UTR leading to reinitation of tranlastion and translation of unintended peptides
36
pausing of the unrecycled 80s at stop codons leads to
ribosome collisions that result in ubiquidation of uS3 that triggers reduction in initiation via 3EHP and braoder activation of the ribosome quality control pathway
37
what gene is affected by inability to recycle ribosomes
GCN4 that activates aa synth genes during starvation and is dependent upon multiple orfs upstream context of uORF1 stop codon favours ribosome scanning and reinitiation and neurites that are particularly sensitve to hcanges in supply of ribosomes
38
what initiation factors play a role in ribosome recycling
eIF3, eIF1, eIF1A, eIF3j
39
how do translation initiation factors work in ribosome recycling
in a biochemically reconstitated system
40
ATP binding casette
ABCE1
41
what other use does ABCE1 have
functions in translation termination by increasing the rate of peptide release
42
what leads to GTP hydrolysis by eRF3
stop codon recognition which also leads to the relase of eRF3
43
how is ABCE1 organized
into multiple domains two NBS
44
what promotes dissociation of the deacylated tRNA
eIF1 and eIF1A
45
what is required for the disociation of mRNA
eIF3j
46
essential for most forms of cap dependent and cap independent translation initiation
eIF3
47
closed loop model
suggest that the proximity of the two ends of mRNA may allow loading of recently recycled ribosomal subunits into the 5'UTR for the next round of initiation
48
what, if left associated with the ribosomal subunits after recycling lays the groundwork for the next round of initiation by recruiting other initiation factors
ABCE1 and eIF3j
49
how was ABCE1 first identified
due to bidning interaction with a key protien in the innate immune response RNaseL
50
what is related in blood disease
ABCE1
51
what is sensitive to mutations in ribosomal proteins
anucleate hematopoietic cells have altered free supply of ribosomes (ribosomeopathies) ABCE1 is reduced in these cells and the loss of recucling efficiency may play a roole in sensitizing these cells to the ribosomal protein mutations
52
tissue specific disorders that reustl from mutations in ribosomal proteins or ribosome biogenesis factors
ribosomaphathies
53
what are some ribosomeopathie diseases
diamond blackfan anemia isolated congenital asplenia treacher collins syndrone
54
infancy, low RBC
diamond blackfan anemia
55
missing spleen= immunodificiency
isolated congential asplenia
56
facial defomities
treacher collins syndrome

3207 (21 decks)

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