Rajarathinam Thanigaimani, Lin Yen Han
Department of Chemical Engineering, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5A9, Canada.
Genomics Proteomics Bioinformatics. 2006 May;4(2):80-9. doi: 10.1016/S1672-0229(06)60020-X.
The underlying principle governing the natural phenomena of life is one of the critical issues receiving due importance in recent years. A key feature of the scale-free architecture is the vitality of the most connected nodes (hubs). The major objective of this article was to analyze the protein-protein and metabolic interaction networks of Drosophila melanogaster by considering the architectural patterns and the consequence of removal of hubs on the topological parameter of the two interaction systems. Analysis showed that both interaction networks follow a scale-free model, establishing the fact that most real world networks, from varied situations, conform to the small world pattern. The average path length showed a two-fold and a three-fold increase (changing from 9.42 to 20.93 and from 5.29 to 17.75, respectively) for the protein-protein and metabolic interaction networks, respectively, due to the deletion of hubs. On the contrary, the arbitrary elimination of nodes did not show any remarkable disparity in the topological parameter of the protein-protein and metabolic interaction networks (average path length: 9.42+/-0.02 and 5.27+/-0.01, respectively). This aberrant behavior for the two cases underscores the significance of the most linked nodes to the natural topology of the networks.
支配生命自然现象的基本原理是近年来受到应有重视的关键问题之一。无标度架构的一个关键特征是连接最多的节点（枢纽节点）的活力。本文的主要目的是通过考虑架构模式以及去除枢纽节点对两个相互作用系统拓扑参数的影响，来分析黑腹果蝇的蛋白质 - 蛋白质相互作用网络和代谢相互作用网络。分析表明，这两个相互作用网络都遵循无标度模型，证实了这样一个事实：来自各种情况的大多数现实世界网络都符合小世界模式。由于枢纽节点的删除，蛋白质 - 蛋白质相互作用网络和代谢相互作用网络的平均路径长度分别增加了两倍和三倍（分别从9.42变为20.93以及从5.29变为17.75）。相反，任意删除节点在蛋白质 - 蛋白质相互作用网络和代谢相互作用网络的拓扑参数上并未显示出任何显著差异（平均路径长度分别为9.42±0.02和5.27±0.01）。这两种情况的异常行为凸显了连接最多的节点对网络自然拓扑结构的重要性。
