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Title: Phase transitions and assortativity in models of gene regulatory networks evolved under different selection processes
We study a simplified model of gene regulatory network evolution in which links (regulatory interactions) are added via various selection rules that are based on the structural and dynamical features of the network nodes (genes). Similar to well-studied models of ‘explosive’ percolation, in our approach, links are selectively added so as to delay the transition to large-scale damage propagation, i.e. to make the network robust to small perturbations of gene states. We find that when selection depends only on structure, evolved networks are resistant to widespread damage propagation, even without knowledge of individual gene propensities for becoming ‘damaged’. We also observe that networks evolved to avoid damage propagation tend towards disassortativity (i.e. directed links preferentially connect high degree ‘source’ genes to low degree ‘target’ genes and vice versa). We compare our simulations to reconstructed gene regulatory networks for several different species, with genes and links added over evolutionary time, and we find a similar bias towards disassortativity in the reconstructed networks.  more » « less
Award ID(s):
1632976
PAR ID:
10286163
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
Journal of The Royal Society Interface
Volume:
18
Issue:
177
ISSN:
1742-5662
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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