Modular co-evolution of metabolic networks.
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.
Zhao
Jing
J
School of Life Sciences & Technology, Shanghai Jiao Tong University, Shanghai 200240, China. zjane_cn@sjtu.edu.cn
Ding
Guo-Hui
GH
Tao
Lin
L
Yu
Hong
H
Yu
Zhong-Hao
ZH
Luo
Jian-Hua
JH
Cao
Zhi-Wei
ZW
Li
Yi-Xue
YX
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*
D020543:Proteome