9. post transcriptional regulation of gene expression II

Question 1

What effect can cytosine deamination to uracil have?

Answer 1

Can alter protein sequences and thus alter protein function

Question 2

Which two proteins are involved in the editing of ApoB?

Answer 2

APOBEC and ACF

Question 3

How is ApoB edited?

Answer 3

cytosine deamination to uracil

Question 4

What protein is involved in Adenine deamination to Inosine?

Answer 4

ADAR

Question 5

What is an example of Adenine deamination to Inosine?

Answer 5

in glutamate receptor subunit GluR-B. Amino acid change from glutamate to arginine
Alters the Ca++ permeability of the channel

Question 6

Reasons RNA editing evolved (3)

Answer 6

System to revise mistakes in transcription
Enhancement of genome/transcriptome plasticity
Once evolved as defense system to inactivate retroviral
mRNA/retrotransposons

Question 7

What can miRNAs do?

Answer 7

stifle production of a protein by interacting with the true mRNA, thereby preventing its translation