Biology Reference
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of the realized effective dynamics, thus already granting practical utility to an imperfect
and incomplete model.
At the academic level, much as a hypothetical generic model of a geographic landscape that
we draw in the classroom teaches us about the basic principles behind the formation of
mountains, valleys, and lakes, but does not help us to navigate the real world to move from
one specific place to another due to the absence of information of the specific geography,
so are we, with regard to gene regulatory networks and cell behaviour, only at the classroom
stage of generic cartoonish models. We do not have all the exact information to compute
the specific potential-landscape topography that could guide us from point (cell state)
A
to
B
. But the formal reduction of valleys and mountains in this landscape that
Waddington already proposed, to the first principles of systems dynamics of a network
provides us now with a solid conceptual framework for the current practice of
reprogramming, much of which is still dominated by brute-force trial-and-error efforts in
perturbing the dynamics of gene-regulatory networks. With sufficient information, as to be
expected in the near future, it may be possible using the theories presented here, to
reconstruct the real-world regulatory epigenetic landscape of model organisms. It can then
serve as a specific road map to design efficient strategies for reprogramming of any desired
cell type at will with high efficiency by computing the optimal starting point and paths.
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