1. Modeling Apoptosis
Miap
Casp6
Casp3 N
NGF-P75

2. NGF
NGF
f(NGF)
p75

3. Miap
Casp6
Casp3 N
NGF-P75

4. LAW OF MASS ACTION

5. Calculus Review > 0 then X is increasing
For us, the concentration vs. time
> 0 then X is increasing
< 0 then X is decreasing

6. Law of Mass Action
Rate of any given chemical reaction is proportional to the product of the concentrations of the reactants.
Example: with reaction rate
Rate of change of concentration of A:
Rate of change of concentration of B:
Rate of change of concentration of C:
[A], [B], concentration of respective chemicals, t is time.

7. A B C +

8. Law of Mass Action (Cont.)
Many reactions are reversible: e.g.
, forward rate constant, , reverse rate constant.
After applying the law of mass action:

9. Wolf
Deer

10. f(NGF)
Miap
Casp6
Casp3

11. When a is positive, c6 will increase forever!

12. Miap
Casp6
Casp3 N
f(NGF)

13. Now what does it do?

14. Simplification
Casp6
Casp3
Miap

15. So what happens?
Casp6
Casp3 N
The Cell May Die

17. So what happens?
Casp6
Casp3 N
The Cell May Live

18. The Casp6 Equation
The Cell May Die
The Cell May Live

19. The Miap Equation

20. Exactly when does the cell die?
Casp6
Casp3 N
Cell Lives When

21. When does the cell die? Cell Lives When Cell Will Probably Die
Casp6
Casp3 N
When does the cell die?
Cell Lives When
Cell Will Probably Die
Cell Will Probably Live