Flashcards in 9.9 Cell Cycle Deck (32):
what does the cell do in G1 phase?
it gathers nutrients and energy. Lives and prepares
what does the cell do in the S phase?
it commits to duplication and division. DNA/organelle replication
what does the cell do in the G2 phase?
it checks and fixes DNA
what does the cell do in M phase?
what are the three locations of the major cell cycle checkpoints?
what causes transition between G1 to S phase?
increase in CycE-Cdk2 levels
CycE-Cdk2 increase levels of what other cyclin?
CycA degrades _____ (what cyclin)
what does CycA do?
it induces DNA replication in S phase
CycB (inactivated) increases and is maximal before ____ phase. It degrades Cyc___.
CyB is regulated by phosphorylation by two enzymes: ______ and ______. Which inhibits and which activates?
CAK - activated
Wee - inhibits
to activate CycB, the inhibitory phosphate needs to be removed by _______.
what activated Cdc25 to dephosporylate the inhibitory phosphate on CycB?
complete and accurate DNA replication
once the inactivating inhibitory phosphate is removed from CycB, what phase transition can happen?
G2 --> M phase
what is the "anaphase wait" signal?
all kinetochores are attached with a microtubule and ready to split
Wee1 inhibits what?
once anaphase is reached, what is expressed? What do they do?
APCs are expressed, they degrade CycB and CycA
what regulates CDKs? (4)
1. cyclin changes (either increase in expression through TFs or degradation such as APCs)
2. Phosphorylation (Wee, CAK)
3. CKIs (CDK inhibitors) in G1
what are CKIs? (p21, p27, etc)
inhibitors of CDK
what is pRB? Is it an oncogene or a tumor suppressor gene?
it is a protein that connects to E2F (on oncogene) and suppresses its activity.
pRB suppresses ______, which is an oncogene.
E2F goes to the nucleus and acts as a TF, expressing ________, inducing which transition?
what oncogene acts as a TF that induces CycE expression, inducing transition from G1 to S phase? what suppresses this?
an oncogenes normal activity is to ______ the cell cycle.
a tumor suppressor gene functions to ______ the cell cycle
RB, p53, p16 (CKIs) are examples of:
tumor supressor genes
myc, ras, raf, cdc25, Cdks, cyclins, EGFR are examples of:
_____/_____ detect DNA damage
ATM/ATRs can activate _____ (a CKI) which assures cells have time to repair damage or if the damage is too extensive, initiate apoptosis
p21 inhibits ____s
reverse in inhibition of ______ allows the cell to progress to M phase from G2 phase