project: signal transduction systems on a cell as a dynamical system

co-worker(s): Ryuzo Azuma, Riken GSC


The signal tralsduction system (STS) is highly complex molecular system in a cell. Although it is one of the major topics in cell biology and a lot of theoretical works are done, we are interested in its dynamical and informatic features.

To investigate dynamical aspect of STS, we aim qualitative understanding of STS dynamics in a broader sense, including artificial networks and parameter ranges. While we do not necessarily concern about exact correspondence to experimental results, we believe understanding of dynamics has more signifiance in a long term.

Majority of theoretical studies on STS employs ODE. However, this method assumes there are sufficiently large number of molecules. We should mention that reactions around the membrane are not necessarily employs sufficient number of molecules and finite size effect may nog neglected. Then we are also working on a model based on Monte-Carlo method to evaluate fluctuation (or any other finite-size effects) explicitly.

So far we have shown that fluctuation obtained Monte-Carlo simulation corresponds to experimental fluctuation of mos response of Xenupus oocyte by Ferrell et. al. [1]. Other models are being developed.

[1]J.E.Ferrell and M.Machleder Science 280 (1998) pp.895-898


publications:

1 submitted

Ryuzo Azuma, Tomoyuki Yamamoto and Akihiko Konagaya
Spatiotemporal dynamics in the mitogen-activated protein kinase cascade
submitted to Proceedings of National Academic of Sciences, USA