Evolutionarily stable and fragile modules of yeast biochemical network

Santra, Tapesh (2011) Evolutionarily stable and fragile modules of yeast biochemical network. PhD thesis, University of Glasgow.

Abstract

Gene and protein interaction networks have evolved to precisely
specify cell fates and functions. Here, we analyse
whether the architecture of these networks affects evolvability.
We find evidence to suggest that in yeast these networks are
mainly acyclic, and that evolutionary changes in these parts do
not affect their global dynamic properties. In contrast, feedback
loops strongly influence dynamic behaviour and are often
evolutionarily conserved. Feedback loops are often found to
reside in a clustered manner by means of coupling and nesting
with each other in the molecular interaction network of yeast.
In these clusters some feedback mechanisms are biologically
vital for the operation of the module and some provide auxiliary
functional assistance. We find that the biologically vital
feedback mechanisms are highly conserved in both transcription
regulation and protein interaction network of yeast. In
particular, long feedback loops and oscillating modules in protein
interaction networks are found to be biologically vital and
hence highly conserved. These data suggest that biochemical
networks evolve differentially depending on their structure
with acyclic parts being permissive to evolution while cyclic
parts tend to be conserved.

• Item Type: Thesis (PhD)
• Qualification Level: Doctoral
• Keywords: Molecular Evolution, Yeast, Systems biology, Protein interaction
• Subjects: Q Science > QR Microbiology; Q Science > QA Mathematics > QA75 Electronic computers. Computer science
• Colleges/Schools: College of Science and Engineering > School of Mathematics and Statistics > Mathematics
• Supervisor's Name: Girolami, Prof. Mark
• Date of Award: 2011
• Depositing User: Mr TAPESH SANTRA
• Unique ID: glathesis:2011-2644
• Copyright: Copyright of this thesis is held by the author.
• Date Deposited: 29 Aug 2011
• Last Modified: 10 Dec 2012 13:58
• URI: http://theses.gla.ac.uk/id/eprint/2644