Cell Cycle: book / slides Flashcards
G1 > S > G2 > M (prophase, metaphase, anaphase, telophase).
Which proteins control transitions to each phase?
G1 >(G1 cyclin-CDKs, SCF induces)> S >> G2 >(Mitotic cyclin-CDKs) > M (prophase > metaphase >(APC/C ubiquitin-protein ligase)> anaphase >(APC/C, Cdc14 phosphatase)>G1
If there is a high environmental temp in the cell cycle, what happens?
Cell cycle is blocked at G1 phase
Are G1-cyclin CDKs involved?
Is SCF involved?
How can we study the cell cycle?
Budding yeast is good (growth at different sections)
Stain / put stuff on cells
Measure DNA
What are the roles of checkpoints in cell cycle control?
What is the role of cyclin in cell cyclel control?
What are the roles of Cdks in cell cycle control?
What factors influence the cell cycle control system?
How do you study amount of DNA content in a given stage?
How much DNA is there in each stage?
Flow cytometer (FACS): Bind to DNA, fluoresces. More fluorescence = more DNA
G1: Lots of cells (2n)
S: Not many cells (2n-4n)
G2: intermediate cell count (4N)
Situation: There is cell-cycle arrest in S phase + apoptosis
You know DNA content
What’s the difference between Situation and a control?
B.
More cells in S phase
More cells with 2n-4n instead of one or the other
Are cyclins always present?
Are Cdks?
Cdk is always there
Cyclin gets made / degraded
When do you see G1/S cyclin?
When do you see S cyclin?
When do you see M-cyclin?
When do you see APC/C?
G1/S: G1-S phase. Cause S phase.
S: All through S-phase up until mid-mitois
M: G2 beginning-metaphase-anaphase
APC/C: Metaphase-anaphase transition
G1 cyclin
G1/S cyclin
S-cyclin
M-cyclin
How many Cdks are there and which does each cyclin bind to?
G1 cyclin: 1, 2
G1/S cyclin: 3
S cyclin: 3, 4
M-cyclin: 4
Do Cdks or cyclins get phosphorylated? What is the benefit?
What transition does Wee1 kinase cause?
Cdks. Activate/inactivate them
What does Wee1 do?
What does Cdc25 do?
Wee1: phosphorylate to inhibit Cdk
Cdc25: dephosphorylate to increase Cdk activity
