Molecular Genetics: Translation Flashcards Preview

Foundations of Biology II > Molecular Genetics: Translation > Flashcards

Flashcards in Molecular Genetics: Translation Deck (24)
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1
Q

prokaryotic vs. eukaryotic ribosomes

A

share a core or some proteins and rRNAs but also have unique proteins and rRNAs

2
Q

antibiotics as translation inhibitors

A

bind to unique proteins in prokaryotic ribosomes - won’t impact translation in human cells

3
Q

polyribosome

A

multiple ribosomes bound to a single mRNA

4
Q

ribosomes bind to which end of the mRNA

A

5’, read mRNA 5’ to 3’

5
Q

mRNP

A

export proteins + mRNA - docks and passes through nuclear pore in eukaryotes

6
Q

tRNA

A

adaptor molecule between amino acids and mRNAs (needed because hydrophobic amino acids can’t interact with negatively charged mRNA)

7
Q

where is the amino acid located on the tRNA

A

the 3’ end

8
Q

aminoacyl tRNA

A

amino acid bonded to its associated tRNA

9
Q

aminoacyl-tRNA synthetase

A

uses ATP to catalyze formation of ester linkage - different enzyme for each amino acid

10
Q

40 tRNAs pair with 61 amino acid coding codons supports

A

wobble hypothesis: flexibility in the third position for codon-anticodon pairing

11
Q

rules for wobble

A

G pairs with U or C
A pairs with U
Inosine pairs with U, C, or A only in tRNA

12
Q

active site in ribosomes

A

composed entirely of catalytic rRNA that aides in peptide bond formation

13
Q

ribozyme

A

RNA capable of acting as an enzyme

14
Q

translation initiation in prokaryotes

A

ribosome binding site binds to small subunit

15
Q

translation initiation in eukaryotes

A

small subunit binds to 5’ cap

16
Q

initiation factors

A

bring in the initial aminoacyl-tRNA

17
Q

translocation

A

ribosome shifts down the mRNA - requires GTP and help from elongation factor proteins

18
Q

translation termination

A

stop codon enters A site and protein release factor binds to the stop codon - ribozyme hydrolyzes ester linkage between tRNA and peptide chain and complex dissociates

19
Q

chaperone proteins

A

aide in protein folding

20
Q

4 methods of post-translational chemical modifications

A

sorting signals, (de)phosphorylation, methylation/acetylation, ubiquitination

21
Q

post-translational sorting signals

A

carb or lipid molecular address labels

22
Q

selenocysteine

A

amino acid that recognizes codon UGA (normally stop codon)

23
Q

how can selenocysteine be inserted into a peptide chain

A

selenocysteine insertion sequence must be in the 3’ UTR and assisting proteins must be present

24
Q

translational recoding

A

when a stop codon is used to insert amino acid - this method is being used by synthetic biologists to expand the genetic code