Lecture 4 : Translation

Question 1

What is an upstream enhancer?

Answer 1

Closer to the 5’ end than the promoter, upstream from promoter, provides binding site for transcription factors enhancing RNA polymerase action

Question 2

Whole thing

Answer 2

UTR = Untranscribed region

Question 3

For understanding

Answer 3

Question 4

What are TATA boxes, CCAAT boxes and GC boxes?

Answer 4

They are part of the PROMOTER and are binding sites for transcriptional factors and RNA polymerases

Question 5

For more understanding of UTRs and start codons etc

Answer 5

Question 6

What are ribosomes?

Answer 6

• Site of translation of mRNA
• 2 subunits (large and small, 60s and 40s)

Question 7

What is tRNA?

Answer 7

Brings amino acids to the ribosomes during translation to be assembled into polypeptide chains

Question 8

How is an amino acid added to an RNA

Answer 8

Enzyme Aminoacyl-tRNA synthetase adds correct amino acid to its tRNA, in a process called AMINOACYLATION or ‘CHARGING’

20 amino acids, so 20 aminoacyl-tRNA synthetases

Question 9

Visualisation of how aminoacyl-tRNA synthetase binds amino acids and tRNA

Answer 9

Question 10

How is translation terminated?

Answer 10

Stop codon reached, release factor reads triplet and polypeptide synthesis finishes. Polypeptide released from tRNA, tRNA releases from ribosome, and 2 ribosomal subunits separate from mRNA

Question 11

Polysomes

Answer 11

When proteins need to be produced quickly

Question 12

Summary initiation of translation

Answer 12

Question 13

Termination of Translation Summary

Answer 13