Cell Division and Apoptosis III Chapter 17
Activation of a cyclin dependent kinase
CdK activity can be suppressed by inhibitory phosphorylation
CdK activity can be suppressed by inhibitory proteins
The Rb protein acts as a brake in mammalian cells
Programmed Cell Death - Apoptosis
Digits in developing mouse paw are formed through apoptosis cells undergoing apoptosis
Apoptosis causes tadpole to lose tail
Necrosis vs. apoptosis
DVD clip 77
Caspase cascade occurs during apoptosis
Procaspase is activated by an active caspase
4 types of intercellular signaling
An animal cell depends on extracellular signals to survive or divide
An animal cell depends on extracellular signals to differentiate. Without extracellular signals the cell will die
Platelet derived growth factor was the first mitogen isolated stimulates cell division during wound healing
Mitogens stimulate G1-Cdk and G1/S-Cdk activities
Ras is activated by tyrosine kinase
p27 suppresses CdK activity
The Rb protein acts as a brake in mammalian cells
Excessive stimulation of mitogenic pathways leads to cell cycle arrest or apoptosis
Cell growth like cell division is also stimulated by extracellular signals
Comparison of nerve cell size vs. lymphocyte size
Fresh medium stimulates cell growth by adding mitogens
Many types of normal animal cells need anchorage to grow and proliferate
cell on small patchcell spread on large patch
Myostatin inhibits proliferation of skeletal muscle cells