Translation in Eukaryotes Patty Kuwabara L22

Question 1

In proks how many NTs above the start codon is the shine delgarno sequence?

Answer 1

8
8Nts upstream of initiator AUG is the shine dalgarno seq recognised by the 16S rRNA - helps to position the ribosome to start translation

Question 2

What does I base pair with?

Answer 2

A, U, C

Question 3

What is the invarient seq at the 3’ end of tRNA?

Answer 3

CCA

encodes adenosine residue which joins the amino acid

Question 4

Which initiation factors in Eukaryotes separate ribosome subunits?

Answer 4

eIF6 (60S)

eIF3 (40S)

Question 5

Which initiation factor provides helicase activity?

Answer 5

eIF4A

Question 6

What are the stages in elongation in translation? EUKS

Answer 6

1) DECODING-A site aminoacyl tRNA selection and binding
2) TRANSPEPTIDATION-transfer peptide chain from P site to A site tRNA
3) TRANSLOCATION-
a) A site tRNA moves to P site.
b) P site tRNA moves to E site
c) E site tRNA is released
d) Ratcheting of mRNA through the ribosome by 1 codon

Question 7

Antibiotic inhibitors of protein synthesis in EUks

Answer 7

Cyclohexamide-Inhibits peptidyl transferase activity of the 60S ribosomal subunit (EUKS)
Puromycin-Causes premature chain termination by acting as an analog of aminoacyl tRNA (PROKS AND EUKS)

Prok inhibitors - good at targeting bacterial infections since they can act specifically on translation processes specific to PROKS

Question 8

Protein secretion and sorting

Answer 8

When you synthesise proteins it will be cytosolic and will be translated on smooth ribosomes
A membrane or secreted protein is made on ribosomes -on the ROUGH endoplasmic reticulum