Translation Younger Flashcards

1
Q

First step in protein synthesis: code contained in a mRNA is put into a particular series of amino acids to form a polypeptide.

A

Translation

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

The protein coding region of an mRNA contains a series of nucleotide triplets called what?

A

Codons

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

How many different orientations are there for codons?

A

4^3= 64 possible codon combinations

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

Nucleotides are read 5’ to 3’ and the protein is synthesized from its __________ (start) to its _________ (end).

A

N-terminus

C-terminus

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

All start codons are ____.

A

AUG

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

True/False: Not every AUG is a start codon.

A

True. only the first AUG encountered (5’ to 3’) is the start codon.

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

AUG encodes for which amino acid?

A

Methionine

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

What are the 3 stop codons? IMPORTANT

A

UGA, UAA, UAG
U go away
U are away
U are gone

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

How many amino acids does this encode for?

5’-Cap- GGGUAGGCCUAUGGACUUAAUAGUAUGUUGAGGCAAAAAA-3’

A

Recognize start site, (counts for 1) + however many amino acids are between start and stop codon (don’t count the stop codon.)
ANSWER: 6 amino acids

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

Each codon is specific for an _________.

A

amino acid

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

True/False: Each amino acid can code for several codon.

A

True, there are as many as 6 codons for a specific amino acid

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

If the DNA sequence is mutated, so that the codon is changed, but still encodes the same amino acid, it is called a _________ mutation.

A

Silent

eg. UCA to UCU both still encode serine

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

If the point mutation results in a codon that defines a different amino acid, is called a ________ mutation.

A

missense

e.g. UCA to UCU- serine to proline

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

If the mutation results in a change from an amino acid to a stop codon, it is called a _______ mutation.

A

nonsense

e.g. UCA to UAA serine to a stop codon

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

If the insertion/deletion is NOT a multiple of 3, the mutation is called a ________ mutation.

A

frameshift

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

IF the insertion/deletion IS a multiple of 3, it results in the ____________ of amino acids.

A

INsertion/deletion

17
Q

This mutation usually results in a premature stop codon and a truncated protein.

A

Frameshift mutation… The closer to the beginning of the protein, generally the more severe the mutation.

18
Q

Regions in a gene where a sequence of bases is repeated many times.

A

trinucleotide repeat expansions

19
Q

Where in the reading frame is a trinucleotide repeat?

A

Both within the cell and outside of the cell. They cause different problems

20
Q

For methionine AUG, what is the anticodon sequence of tRNA that would bind to codon and deliver amino acid? IMPORTANT

A

what is the direction?

5’ AUG 3’—- in 5’ to 3’ direction CAU

21
Q

What enzymes recognize amino acids and all of the tRNAs so that they attach amino acids to the corresponding tRNA.

A

Aminoacyl-tRNA synthetases

dictionary/translator from amino acid to codon sequence

22
Q

How many different aminoacyl-tRNA synthetases are in humans?

A

20

23
Q

How many Pi bonds are broken to get amino acids onto DNA?

A

2 inorganic phosphates are cleaved and let go

24
Q

RIbosome site that binds an incoming aminoacyl-tRNA.

A

A site

25
Q

Ribosome site that binds peptidyl-tRNA.

A

P site

26
Q

Ribosome exit site, contains empty tRNA as it is about to exit the ribosome (note, eukaryotic ribosomes do not contain this site)

A

E site

27
Q

Protein that is generated on the ribosome that is associated with the ER is what? important

A

Secretory proteins

28
Q

Charging the tRNA, 2 high energy bonds from ___ (energy).

A

ATP

29
Q

Binding the aminoacyl-tRNA to the A site is from one ___ (energy).

A

GTP

30
Q

Translocation step- movement of the ribosome to the next codon- uses one ___ (energy).

A

GTP

31
Q

A total of how many high energy bonds are required for each amino acid that is added?

A

4

32
Q

tRNAs can recognize more than one codon for a specific amino acid… What is the name of this hypothesis?

A

Wobble hypothesis
baby
Wobble
baby wobble baby wobble… Get in there

33
Q

Difference between polycistronic and monocistronic…

A

polycistronic- (mRNA could have multiple genes associated with it) prokaryotes
monocistronic- eukaryotes

34
Q

What in the small subunit contains a sequence complementary to the shine dalgarno sequence that allows correct alignment of the small ribosomal subunit with the AUG start codon.

A

16s rRNA

35
Q

The vey first methionine after start codon (AUG) is going to be a _________ methionine.

A

Formylated

36
Q

General understanding of Translation, translocation of 3 nucleotides to the next codon.

A

A site empty, Formylated Meth in P site (holding site), next tRNA is put on A site and ribosome moves down RNA, and tRNA enters into the polypeptide chain.

37
Q

Once you have a stop codon what signals happen?

A

termination step begins.