Let's Split!
The function of mitogens
What is to induce a cell into cell division?
These signals make cells bigger by helping them build proteins and stop breaking them down.
What are growth factors?
This is the function of Survival Factors (300 pts)
What is suppress apoptosis-promoting factors? OR What is promote apoptosis-suppressing factors ?
NGF
What is Growth Factors?
When survival signals fail to regulate the Bcl‑2 family, cells undergo this fate.
What is apoptosis?
The specificity of mitogens
What is non-specific (broad)?
Growth Factors make sure cells don't just divide, but maintain this property.
What is the correct size?
True/False: “If deprived of such survival factors, cells activate their intracellular death program and die by necrosis”
What is False?
Bonus 100 pts: Why is it False?
PHA (phytohemagglutinin)
What is a Mitogen?
This enzyme adds a phosphate to lipids in the plasma membrane, starting a growth signal cascade.
What is PI3K?
The downstream pathway that is activated (hint: discussed before)
What is MAPK?
Growth factors begin their effects by binding to these structures, which activate intracellular signaling pathways.
What are cell surface receptors?
Name 1 cell type that shows survival factors frequently
What are Nerve cells?
NT3 (Neurotrophin-3)
What is Survival Factors?
Together the PI3K and MAPK pathways promote growth and this.
What is proliferation?
One of two receptors activated by mitogens
What are Receptor Tyrosine Kinases or G-protein Coupled Receptors?
Growth factors often activate two major intracellular signaling pathways: PI3K and this kinase cascade. (hint: we talked about this one!)
What is the MAPK pathway?
Name 1 pathway that survival factors control
What is the Bcl2 pathway?
Con A (Concanavalin A)
What is a Mitogen?
Together, PI3K, S6 kinase, and eIF4E activation lead to this overall cellular outcome.
What is increased cell size and growth?
The cells that are most affected by mitogens
What are lymphocytes?
Growth factors increase protein production by turning on this translation initiation factor.
What is eIF4E?
This is another purpose for survival factors ASIDE from preserving certain cells?
What is controlling cell numbers?
PDGF
What is a Mitogen AND Growth Factor?
Mitogen binding to receptor tyrosine kinases activates Ras, which triggers this kinase cascade leading to transcription of cyclin genes.
What is the MAPK/ERK pathway?