Cell Cycle Regulation Flashcards
What is cohesin?
Protein that holds the sister chromatids together
What is the mitotic spindle fiber phase for?
To check if the spindle fibers are attached to BOTH sides of the kinetochore (centromere)
What is needed for SPF to happen?
Cell 2x its size
growth rate = adequate
Presence of growth factors
What are histones?
Protein found in chromatin
What phase is after SPF (if all the factors are ok)?
S-Phase (dna rep. )
What is called the phase to verify if the division is possible/required?/
S-checkpoint/ g1 arrest phase
What is needed to activate MPF?
M-checkpoint:
- cell mass ok (all contents of the cell are there)
- Growth rate ok
- Time elapsed ok
- if DNA replication was made perfectly
What is called the phase to check if the DNA replication was succesful?
M checkpoint/ G2 arrest
What happens with the cell division in cancer? Why is cancer so hard to stop?
The cells duplicate even if they don’t have all the growth factors ok (uncontrolled division)
What happens if SPF does not happen (not produced)?
cell cycle stops, stays in G1
What happens when MPF is activated?
- Chromatin condenses to chromosomes
- breakdown of nuclear membrane
- assembly of mitotic spindles
What happens when MSP checkpoint is OK? (explain)
APC activates:
- allows chromosomes to seperate
- inactivates MPF
What happens when APC inactivates MPF?
- nuclear membranes reform
- chromosomes decondenses
- spindle fibers break down
