Cell Cycle Signalling

Question 1

The cell cycle is regulated by

Answer 1

Cyclins and CDK’S

Question 2

Cyclin D binds to which CDK and is reponsible which activation of the cell cycle

Answer 2

Cdk4 and cdk6; activation of the G1 phase

Question 3

Cyclin E binds to_________and activates the______ phase of the cycle

Answer 3

Cdk2; G1/S

Question 4

Cyclin A binds to________and activates the

Answer 4

Cdk1 and Cdk2; S phase of the cycle

Question 5

Cyclin B binds to_________and activates the_______of the cycle

Answer 5

Cdk1; M phase

Question 6

This enzyme converts CDK from partly active to fully active

Answer 6

CAK (cdk activating kinase)

Question 7

Cyclin levels are what rise and fall while CDK concentrations are what remain the same. T/F

Answer 7

True

Question 8

P27 is a CDK______that acts via conformational change and is used in the_________checkpoint

Answer 8

Inhibitor; G1

Question 9

This enzyme inhibits CDK via phosphorylation and is used in the G2 checkpoint

Answer 9

Wee1

Question 10

This enzyme removes the phosphate on CDK on the roof of the active site that was placed by Wee1 resulting in the reactivating of CDK-Cyclin complex

Answer 10

Cdc25

Question 11

APC/C is a ______which is activated by

Answer 11

Ubiquitin ligase; Cdc20

Question 12

APC/C recruits Ubiquitin enzymes______which poly ubiquinates cyclins

Answer 12

E1 and E2; A and B

Question 13

APC/C activation permits these mitosis stages to occur

Answer 13

Metaphase and anaphase

Question 14

High levels of this cyclin CDK complex inactivates APC/C

Answer 14

Cyclin E-Cdk2

Question 15

Cyclin D is used in all cells. T/F

Answer 15

False

Only used in so,e cells via stimulation by mitogens

Question 16

The enzyme TOR is activated by______and activates the enzyme_______Which phosphorylated the ribosomal protein S6. Resulting in increasing translation of ribosomal proteins

Answer 16

PIP3; S6K

Question 17

The enzyme TOR inhibits________which inhibits eIF4E which inevitably increases the availability eIF4E to increase translation of mRNA to protein

Answer 17

4E-BP

Question 18

The signalling of TOR is a ______Checkpoint

Answer 18

G1

Question 19

Myc is a______that is activated via the MAP kinase cascade which promotes the formation of Cyclin______and thereby activation of G1-cdk

Answer 19

Transcriptional regulator; D

Question 20

Activation of G1-CDK by Cyclin D activates the________to release the E2F protein which promotes S-phase gene products and of cyclin E and A

Answer 20

Retinoblastoma protein

Question 21

Cyclin E-Cdk2 and Cyclin A-cdk1/cdk2 further phosphorylates______to further express E2F

Answer 21

Rb protein

Question 22

P53 activates________in the presence of excessive Myc production

Answer 22

Cell cycle arrest or apoptosis

Question 23

P53 is activated through the release of its binding to_______which is happens via the enzyme_________as a result of excessive Myc production

Answer 23

Mdm2; Arf;

Question 24

Activation of E2F is involved with which checkpoint

Answer 24

G1/S

Question 25

For what reason would cell cycle arrest(p53) be induced

Answer 25

DNA damage

Question 26

DNA damage leads to the activation of______which in turn activates______ and results in phosphorylation of p53, activating it and releasing it from Mdm2

Answer 26

ATM/ATR kinases

Question 27

Phosphorylated p53 acts as a transcription regulator and increases the production of_____, a CDK inhibitor protein.

Answer 27

P21

Question 28

The production of microtubules is the primary synthetic product in this phase of the cycle

Answer 28

G2

Question 29

This CDK-Cyclin complex is the mitosis promoting factor

Answer 29

Cdk1-Cyclin B

Question 30

Cdk1-Cyclin B is activated by

Answer 30

Cdc25

Question 31

Failure to attach spindles during metaphase and anaphase leads to the blocking of________

Answer 31

APC/C activation