7. Cdk/cyclin complexes

Question 1

Which points is the cell cycle controlled at?

Answer 1

G2/M
M/A
Restriction point
G1/S

Question 2

How are Cdks inactive in absence of cyclin subunit?

Answer 2

The T loop of the Cdk occludes the catalytic active site

Question 3

What does p16INK do?

Answer 3

Blocks Cyclin D association to Cdk4

Question 4

What does p27 do?

Answer 4

Blocks ATP binding by Cyclin A/Cdk2 complex

Question 5

What does p21 do?

Answer 5

Blocks substrate binding by both Cdk1/Cyclin and Cdk2/Cyclin complexes

Question 6

Mitotic cyclin-Cdks

Answer 6

Cyclin A-Cdk1

Cyclin B - Cdk1

Question 7

Mid G1 cyclin-Cdks

Answer 7

Cyclin D-Cdk4

Cyclin D- Cdk6

Question 8

Late G1 cyclin-Cdk

Answer 8

Cyclin E-Cdk2

Question 9

S phase cyclin-Cdk

Answer 9

Cyclin A-Cdk2

Question 10

How is cyclin B/Cdk1 activity inhibited during G2?

Answer 10

Phosphorylation of tyrosine 15 in the ATP binding pocket of Cdk1 by Wee1 kinase