Transcript section9

SECTION 9
SPATIAL PROBLEMS III:
BREAKING SYMMETRY
THE MODEL
QUESTION 1
What is the critical value of kl/ks, above which the system is bistable?
QUESTION 1
What is the critical value of kl/ks, above which the system is bistable?
QUESTION2
Brefeldin A (BFA) is a drug that disrupts the Golgi apparatus by
collapsing the compartments. How can you use this program to
simulate recovery from BFA treatment. Can this system recover from
BFA treatment? For what range of kl/ks?
QUESTION3
We have seen in Question 1 that the cell would like kl/ks to be large in
order to generate two distinct compartments. What happens to the
system when kl/ks gets very large? Think in terms of the fluxes (the
rate at which vesicles that bud from one compartment fuse to the
other. What value of kl/ks optimizes the directional flow between the
two compartments?
HINT:
Flux of vesicle A from S1 to S2 = fa1 = xua1*xu2 + yva1*yv2
fb1 = xub1*xu2 + yvb1*yv2
fa2 = xua2*xu1 + yva2*yv1
fb2 = xub2*xu1 + yvb2*yv1
QUESTION 1
QUESTION 2
QUESTION 3