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Duplication-divergence model of protein interaction network

I. Ispolatov·P. L. Krapivsky·A. Yuryev
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Abstract

We show that the protein-protein interaction networks can be surprisingly well described by a very simple evolution model of duplication and divergence. The model exhibits a remarkably rich behavior depending on a single parameter, the probability to retain a duplicated link during divergence. When this parameter is large, the network growth is not self-averaging and an average vertex degree increases algebraically. The lack of self-averaging results in a great diversity of networks grown out of the same initial condition. For small values of the link retention probability, the growth is self-averaging, the average degree increases very slowly or tends to a constant, and a degree distribution has a power-law tail.

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I. Ispolatov, P. L. Krapivsky, A. Yuryev. 2004-11-30. Duplication-divergence model of protein interaction network. https://doi.org/10.1103/physreve.71.061911

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