Brainscape's Knowledge GenomeTM

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


See full index

MCM exam 2 > Protein processing > Flashcards

Protein processing Flashcards

1
Q

What is the RNA start codon for translation and what does it code for?

A

AUG- Methionine

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

What are the three RNA stop codons

A

UAA, UAG, UGA

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

What is a silent mutation?

A

A mutation that does not result in a change in the amino acid

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

What is a missense mutation?

A

A mutation that results in a change in the AA that can either have no effect or drastic change in protein folding

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

What is a nonsense mutation?

A

A mutation that changes the codon to a stop codon resulting in premature termination of protein synthesis

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

What is a frameshift mutation?

A

A mutation that causes multiple changes to the codon sequence

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

What is the mutation in sickle cell anemia and the physiological effect?

A

Glu (hydrophilic) to Val (hydrophobic) at the human beta globin gene. This results in deformed proteins that are rod-like and will aggregate. These cells have poor oxygenation and will clog arteries.

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

What kind of mutation results in sickle cell anemia?

A

a missense mutation- Glu for Val- results in misfolded protein

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

What is Duchenne Muscular Dystrophy?

A

Dystrophin gene is dysfunctional due to an out of frame mutation- Leads to muscle wasting and death

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

What kind of mutation results in Duchenne Muscular Dystrophy?

A

An out of frameshift mutation that leads to non functioning dystrophin gene

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

What kind of mutation results in Becker Muscular Dystrophy?

A

An in frame mutation of the dystrophin gene that results in a truncated dystrophin protein

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

What two things are added to mRNA to “protect” the sequence?

A

5’cap and poly A tail

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

What is the secondary structure and two crucial sites of the tRNA?

A

Shaped like a cloverleaf with an anticodon region to pair with complementary strand and 3’CCA terminal region that binds the AA for corresponding codon

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

How do tRNAs become activated?

A

Through aminoacyl synthetases- uses ATP to bond tRNA to the COOH end of the AA

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

What are the ribosomal subunits in prokaryotes?

A

50S large subunit and 30S small subunit- 70s when combined

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

What are the ribosomal subunits in eukaryotes?

A

60s large subunit and 40s small subunit- 80s when combined

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

What are the three sites of ribosome complex?

A

A- acceptor
P- peptidyl
E- exit

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

What are the steps involved in the initiation process of protein synthesis? Name the proteins involved

A

Met-tRNA is bound to GTP and loaded into the p site of the small subunit of the ribosome- other TF are added- (eIFs for euk and IFs for prok)- The large subunit will then bind and translation begins.

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

What are the steps involved in the elongation process of protein synthesis? Name the proteins involved and bonds formed

A

Aminoacyl tRNA is bound to a GTP elongation factor then loaded into the A site of ribosome. GTP hydrolysis and release of factor occur then peptidyl transferase will form a peptide bond between AA of a site and p site.

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

What are the steps involved in the termination process of protein synthesis? Name the proteins involved

A

RFs will recognize the stop codon at A site of ribosome and bind. Cleavage of the ester bond between the c terminus of peptide chain and tRNA. This releases the protein and GTP hydrolysis causes complex to disassociate.

21
Q

polysomes

A

cluster of ribosomes that will translate a strand of mRNA simultaneously. Allows for increased protein production

22
Q

What is the effect of streptomycin on protein synthesis?

A

Binds to the 30s subunit of prokaryotes to disrupt initiation- fmet-tRNA binding and association of 50s and 30s subunits

23
Q

What is the effect of Tetracycline on protein synthesis?

A

Binds to the 30s subunit of prokaryotes to disrupt elongation- prevents entry of animoacyl tRNA to ribosome complex

24
Q

What is the effect of Chloramphenicol on protein synthesis?

A

inhibits peptidyl transferase during elongation (prokaryotes)

25
Q

What is the effect of clindamycin and erythromycin on protein synthesis?

A

binds to the large 50s subunit and prevents translocation of the ribosome during elongation

26
Q

What is the effect of cyclohexamide on protein synthesis?

A

Inhibits peptidyl transferase in euks during elongation

27
Q

What is the effect of diphtheria toxin on protein synthesis?

A

inactivates GTP bound eEF-2 interfering with ribosome translocation during elongation

28
Q

What is the effect of Shiga Toxin and ricin on protein synthesis?

A

binds to large 60s subunit, blocking entry of aminoacyl tRNA to ribosome in elongation

29
Q

What is the effect of puromycin on protein synthesis?

A

causes premature chain termination in both euks and proks- resembles the 3’ end of aminoacyl-tRNAs so added to the chain but causes the chain to be released when puromycylated chain formed.

30
Q

What is the cytoplasmic pathway of protein sorting?

A

involves proteins destined for the cytoplasm, nucleus, peroxisome and mitochondria- synthesis begins/ends on free ribosomes and translocation signal will determine final destination

31
Q

What is the secretory pathway of protein sorting?

A

involves proteins destined for the ER, secretion, lysosome and plasma membrane. synthesis begins with free protein but ends in the ER. Translocation signal will determine final destination

32
Q

What is the translocation signal for the nucleus during protein sorting?

A

Lysine and Arginine rich signal- KKKRKRR

33
Q

What is the translocation signal for the cytoplasm during protein sorting?

A

There is no translocation signal

34
Q

What is the translocation signal for the peroxisome during protein sorting?

A

SKL signal- Serine, Lysine and Leucine

35
Q

What is the translocation signal for the mitochondria during protein sorting?

A

N terminus hydrophobic alpha-helix signal- uses this to associate with chaperone proteins. Further sorting by TIM and TOM when at mitochondria

36
Q

What is the translocation signal for the ER during protein sorting?

A

Starts originally with N terminus hydrophilic alpha helix signal then further sorting with KDEL signal

37
Q

What is the translocation signal for the lysosome during protein sorting?

A

Starts originally with N terminus hydrophilic alpha helix signal then further sorting with mannose-6-phosphate

38
Q

What is the translocation signal for the plasma membrane during protein sorting?

A

Starts originally with N terminus hydrophilic alpha helix signal then further sorting with N terminal a polar signal

39
Q

What is the translocation signal for the secretion during protein sorting?

A

Starts originally with N terminus hydrophilic alpha helix signal then further sorting with tryptophan rich signal

40
Q

What is I-cell disease?

A

A disorder that results from the protein that tags lysosome proteins with a mannose 6P being defective. The proteins will remain in the cytosol. Death a premature age

41
Q

What is the difference between chaperones and chaperonions?

A

Chaperons assist in the folding of large proteins while chaperonions are barrel shape protein that help the folding of proteins using ATP hydrolysis.

42
Q

What is acetylation?

A

The adding of an amine group to a protein on a lysine residue as a form of posttranslational modification

43
Q

What is glycosylation?

A

Two types; O- glycosylation and N-glycosylation
O-glycosylation is the addition of a hydroxyl group to a serine
N-glycosylation is the addition of an amine group to Asn of Gln

44
Q

What is a disulfide bond?

A

oxidation to achieve sulfide linkage of cysteine residues

45
Q

What is phosphorylation?

A

Esterification of a hydroxyl group at Ser, Tyr or Thr

46
Q

Alzheimer’s disease

A

amyloid precursor protein (APP) breaks down and forms amyloid beta peptide. This protein will then midfold and aggregate in the brain (extracellular). Misfolded proteins also result in the hyperphosphorylation of Tau resulting in cellular death (intracellular).

47
Q

Parkinson’s disease

A

aggregation of alpha-synuclein form lewy bodies in dopaminergic cells in substantia nigra. Death of these cells and reduced levels of dopamine result.

48
Q

Huntington’s disease

A

Mutation in the Huntingtin gene that results in CAG triplet repeats. There are polyglutamine repeats that result in midfolded proteins and aggregation. Cell death in the basal ganglia.

49
Q

Crutzfeldt-Jacob disease

A

misfolding of prion proteins. The midfolded proteins result in cell death and a spongiform encephalopathies. Prions are also able to convert normal folded proteins to the prion form.

MCM exam 2 (13 decks)

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