| Abstract: |
| Dynamics of gene activities based on gene regulatory networks are the origin of biological functions. To understand dynamics of complex systems, we developed Linkage Logic theory by which important aspects of dynamics are determined from topology of regulatory network alone. The theory assures that i) any dynamical behavior of whole system can be identified/controlled by a subset of nodes in a regulatory network, and ii) the subset is determined from topology of the network as a feedback vertex set (FVS). We applied the theory to gene regulatory network for ascidian development including >90 genes. We verified our prediction by experimental manipulation of six genes, and confirmed deterministic induction of each of all seven tissues, respectively.
To expand the practical power of Linkage Logic, we also developed new estimation method for gene regulatory networks called RENGE, where genes are perturbed comprehensively and resulting changes in gene expression are measured as a time series. This method makes it possible to distinguish between direct and indirect regulations. This method was applied to human iPS cells, and a gene network containing 103 genes for pluripotency was estimated. We are currently working on fate control of human iPS cells by manipulating FVS of the network. |
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