Hello,
I am new to this group but the question put by Mr Brand made me share with
you the things we do here at the Dept. of Radiobiology. We are modelling
the SOS regulatory network in E. coli: there's one common repressor of a
set of genes which is destroyed after DNA damage thus allowing SOS genes
expression. DNA repair helps return a cell to normal condition followed by
repressor
accumulation and SOS genes shut-off.
What I have done may seem trivial to you: since it is the concentration of
the repressor that controls the whole thing, I thought writing
differential
equations for concentrations of interplaying proteins (repressor in the
first place) would be the right thing to do. And indeed, simulation
provides an
overview of the regulatory system kinetic behaviour + results agree with
experimental data on repressor kinetics. The paper on this subject is
going to
appear in J. Theor Biol. soon.
Now, the question is how can MCA be applied to such a system? I am ashamed
to say that I know little of MCA but I feel it'll be useful here with this
particular problem since there are some kinetic data + pathways are known
in detail. Simulation is okay but when one wishes to go a little further
in investigation he needs more elaborative approach.
And, modelling the SOS system seems to be also important from the
practical point of view: there's an apparatus being constructed by an
international group (we participate) on the basis of E. coli's SOS system
to monitor the mutagenic pressure of the environment.
Sincerely,
--
Sergei Aksenov
Ph.D. student
Dept. of Radiobiology, JINR
141980 Dubna, Moscow reg., Russia
