Gene Organisation and Transcription 2

Question 1

How many RNA polymerases do bacteria have?

Answer 1

1

Question 2

What bases do introns start and end with?

Answer 2

start = GU, end = AG

Question 3

Describe CAP structure addition

Answer 3

post-transcriptional addition of CAP to 5’ end of mRNA
formed by hydrolysis of terminal triphosphate of mRNA to diphosphate
diphosphate reacts with phosphate of GTP to form 5’-5’ phosphate link

Question 4

What is the purpose of the CAP?

Answer 4

protects mRNA at 5’ end and enhances translation

Question 5

What does polio do?

Answer 5

interferes with CAP recognition in translation

Question 6

What is polyadenylation?

Answer 6

addition of poly-A tail to pre-mRNA

Question 7

How is a poly-A tail added?

Answer 7

one base at a time, 11-30 bases down from AAUAA sequence

Question 8

What is the poly A tail purpose?

Answer 8

increase stability

Question 9

What is thalassaemia?

Answer 9

imbalance in relative alpha and beta chains in Hb

Question 10

What is beta thalassaemia caused by?

Answer 10

splice site mutation in beta globing gene

Question 11

What are thalassaemia features?

Answer 11

iron overload (cirrhosis, skin darkening), hepatomegaly, extra medullary hemapoiesis