The Effect of Sequence Complexity on the Construction of Protein-Protein Interaction Networks

  • Mehdi Kargar
  • Aijun An
Part of the Lecture Notes in Computer Science book series (LNCS, volume 6334)


In this paper, the role of sequence complexity in the construction of important nodes in protein-protein interaction (PPI) networks is investigated. We use two complexity measures, linguistic complexity and Shanon entropy, to measure the complexity of protein sequences. Three different datasets of yeast PPI networks are used to conclude the results. It has been shown that there are two important types of nodes in the PPI networks, which are hub and bottleneck nodes. It has been shown recently that hubs and bottlenecks tend to be essential in the process of evolution. Better understanding of the properties of these two types of nodes will shed light on why proteins interact with each other in the observed manner. We show that the sequence complexity of hubs are lower than that of non-hubs. But the difference is not significant in most cases. On the other hand, the sequence complexity of bottlenecks are lower than that of non-bottlenecks and the difference is significant in most cases. Modularity has an effective role in the construction of PPI networks. We find that there is no significant difference in the node complexity among different modules in a PPI network.


Complexity Measure Sequence Complexity Biological Sequence Average Complexity Important Node 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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© Springer-Verlag Berlin Heidelberg 2010

Authors and Affiliations

  • Mehdi Kargar
    • 1
  • Aijun An
    • 1
  1. 1.Department of Computer Science and EngineeringYork UniversityOntarioCanada

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