Lecture 7 + 8

Question 1

DNA damage may result in which of the following

Answer 1

a. DNA double strand breaks
b. Increased levels of p53 protein
c. Increased activation of ATM
d. Increased activation of Chk1/Chk2

Question 2

TP53 is a tumour suppressor gene encoding the p53 protein. What are the functions of the p53 protein?

Answer 2

a. Regulate DNA damage repair
b. Halt the cell cycle
c. Induce apoptosis
d. Function as a transcriptional activator and repressor

Question 3

Are p53 mutated in a high percentage of cancers

Answer 3

Yes

Question 4

How does p53 bind to DNA

Answer 4

As a tetramer

[A tetramer (tetra-, “four” + -mer, “parts”) is an oligomer formed from four monomers or subunits.]

Question 5

Does p53 induces PUMA and APAF-1

Answer 5

Yes

Question 6

Increased expression of MDM2 may result in

Answer 6

Degradation of p53

Question 7

p53 is activated in response to DNA damage-Name
the kinases involved

Question 8

How does the above (1.) relate to p53 protein levels?
ie what happens to p53 levels following DNA damage?

Question 9

. p53 can block cell cycle progression at G1 and G2MHow? What are the main targets-what happens here

Question 10

Mutant p53 acts in a dominant negative manner to
block wt p53-can you explain?

Question 11

. Describe role of p53 in Apoptosis