title: Modular co-evolution of metabolic networks.
abstract: BACKGROUND
  The architecture of biological networks has been reported to exhibit high level of modularity, and to some extent, topological modules of networks overlap with known functional modules. However, how the modular topology of the molecular network affects the evolution of its member proteins remains unclear.
  
  
  RESULTS
  In this work, the functional and evolutionary modularity of Homo sapiens (H. sapiens) metabolic network were investigated from a topological point of view. Network decomposition shows that the metabolic network is organized in a highly modular core-periphery way, in which the core modules are tightly linked together and perform basic metabolism functions, whereas the periphery modules only interact with few modules and accomplish relatively independent and specialized functions. Moreover, over half of the modules exhibit co-evolutionary feature and belong to specific evolutionary ages. Peripheral modules tend to evolve more cohesively and faster than core modules do.
  
  
  CONCLUSIONS
  The correlation between functional, evolutionary and topological modularity suggests that the evolutionary history and functional requirements of metabolic systems have been imprinted in the architecture of metabolic networks. Such systems level analysis could demonstrate how the evolution of genes may be placed in a genome-scale network context, giving a novel perspective on molecular evolution.
authors.affiliation: School of Life Sciences & Technology, Shanghai Jiao Tong University, Shanghai 200240, China. zjane_cn@sjtu.edu.cn
authors.forename: Jing
authors.initials: J
authors.lastname: Zhao
authors.forename: Guo-Hui
authors.initials: GH
authors.lastname: Ding
authors.forename: Lin
authors.initials: L
authors.lastname: Tao
authors.forename: Hong
authors.initials: H
authors.lastname: Yu
authors.forename: Zhong-Hao
authors.initials: ZH
authors.lastname: Yu
authors.forename: Jian-Hua
authors.initials: JH
authors.lastname: Luo
authors.forename: Zhi-Wei
authors.initials: ZW
authors.lastname: Cao
authors.forename: Yi-Xue
authors.initials: YX
authors.lastname: Li
mesh_terms: D003198:Computer Simulation; D019143:Evolution, Molecular; D015894:Genome, Human / Q000235:genetics*; D006801:Humans; D008957:Models, Genetic; D020543:Proteome / Q000235:genetics*; D015398:Signal Transduction / Q000235:genetics*
chemical_list: D020543:Proteome