Environmental Control of the Cell Cycle Flashcards
How is plant growth different to animal growth?
Plant growth is adapted to the environment.
What does increased CycD cause?
Increased cell division and therefore plant growth rate.
What is the cell cycle controlled by?
Cyclins and cyclin dependent kinases (CDKs)
What does the interaction between Rb and EF2 cause?
When Rb is bound to EF2, it is inactive and therefore the cell does not proceed to S phase.
When Rb is not bound to EF2, it is active and therefore the cell does proceed to S phase.
Outline cell cycle G1 regulation.
CycD and CDK bind
CycD and CDK complex phosphorylates Rb, changing its conformational shape.
Rb does not bind to EF2, so it is active and the cell proceeds to S phase.
What is ICK1?
Inhibitor of CDK
How does sugar regulate the cell cycle?
Sucrose triggers CycD 2/3 expression which drives cell progression through G1
What does CycD 4 activate?
Expression in root pericycles.
How does auxin regulate the cell cycle?
Auxin regulates root development indirectly in the cell cycle via multiple pathways:
- CycD/CDK complex
- Series of steps involving transcription factors.
Where is the mitotic checkpoint?
Between metaphase and anaphase
Outline cell cycle M regulation (in comparison to cell cycle G1 regulation).
Similar to G1 but different cyclins and CDKs involved: CycA/B, CDKA/B.
And Rb is substituted with APC (anaphase promoting complex)
CycA/B CDKA/B complex degrades APC, progressing mitosis
How does Co2 regulate the cell cycle?
Increased Co2:
- Increased number of cells dividing
- Decreased G1 and G2 length
- Faster growth
