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Flashcards in lecture 1 Deck (14)
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1

what order is the cell cycle

G1, S, G2, M

2

what cyclins are at what points of cell cycle

G1: CDK4/6 + cyclin D(1-3)
after R point: CDK2 + cyclin E
S: CDK2 + cyclin A then CDC2 + cyclin A
G2: CDC2 + cyclin B
M: CDK2 + cyclin B

3

what are the two major control factors in cell cycle control

normal control by cyclins
mechanisms that stop the cycle

4

how do the cyclin levels fluctuate

Cyclin E: low in G1, rapid increase after R
Cyclin A: increase as entry to S phase
Cyclin B: increase before m phase

5

what is the exception to cyclin ubiquitination as the cell cycle goes on

Cyclin D
expressed in G1 and is controlled by growth factors
other cyclins are controlled by IC signals

6

CKI

cyclin inhibitor = 7 proteins that antagonise CDK/cyclin activity

7

what happens at G1 checkpoint

is cell big enough
is environment favourable
DNA damage

8

what happens at G2 checkpoint

is all DNA replicated
is cell big enough
is environment favourable

9

what happens at metaphase checkpoint

are all chromosomes on spindle

10

where in the cell cycle can DNA damage be detected

G1, entry to S phase, entry to mitosis

11

how is DNA repaired in G1

NHEJ

12

how is DNA repaired in G2

HR

13

DNA damage response in G1

p53 - p21
inhibits S-CDK complexes
DNA is repaired
if DNA cant be repaired = apoptosis

14

what is different in embryos

cyclin E and A are high in wrong phasers