Al-Mehdi Cell Cycle Flashcards
this phase is the growth phase and lasts on ave. 11 hours
G1
this phase deals w/ DNA synthesis and lasts on ave. 8 hours
S phase
cell prepares to divide in this phase (prepares for mitosis); lasts on ave. 4 hours
G2
how long does M phase last
1-2 hrs
this phase is where cells exit or re-enter or they just stay here
G0
neurons, skeletal and cardiac m, RBC’s stay in this phase
G0
hepatocytes, lymphocytes, PCT, periosteal cells are stable in G0, but can reenter into what phase
G1
what causes side effects of cancer drugs
the drugs target rapidly dividing cancer cells and normal cells and travel in hte blood so it effects whole body, especially the organs that have rapidly dividing cells
bone marrow, gut epithelium, skin, and hair follicles, and germ cells are never in this phase b/c rapidly dividing
G0
checkpoint for DNA damage
G1/S
checkpoint for unduplicated DNA
G2/M
checkpoint for proper attachment of chromosomes to mitotic spindle
Mitotic Spindle checkpoint
policeman of G1/S checkpoint
Rb (retinoblastoma protein)
CDKs do what to Rb for cell cycle to proceed
phosphorylate
what has to bind to Rb for progression to S phase
Cyclin D and CDK4/6
S phase cyclins and CDKs
Cyclin E and CDK2
Cyclin A and CDK2
G2 phase cyclins and CDKs
Cyclin A and CDK2
Cyclin B and CDK1
MS phase cyclin and CDK
Cyclin B and CDK1
CDK inhibitors (CDKIs) of CDK 4/6
p15, p16
CDK inhibitors (CDKIs) of multiple CDKs
p21
this protein is guardian of genome and senses a problem and stops cell cycle
p53
what protein activates CDKIs if there is a problem in cell cycle; arrests cell in G1
p53
DNA damage checkpoint:
- phosphorylate p53 and mdm2 by ATM
- p53 separates from mdm2
- cell cycle arrest (CDKIs)
special agents that sense if damage is beyond repair and control BCL-2 expression
BAD/BID/BIM