Artefacts in statistical analyses of network motifs: general framework and application to metabolic networks

M. E. Beber, C. Fretter, S. Jain, N. Sonnenschein, M. Muller-Hannemann, M.-T. Hutt
2012 Journal of the Royal Society Interface  
Few-node subgraphs are the smallest collective units in a network that can be investigated. They are beyond the scale of individual nodes but more local than, for example, communities. When statistically over-or under-represented, they are called network motifs. Network motifs have been interpreted as building blocks that shape the dynamic behaviour of networks. It is this promise of potentially explaining emergent properties of complex systems with relatively simple structures that led to an
more » ... terest in network motifs in an ever-growing number of studies and across disciplines. Here, we discuss artefacts in the analysis of network motifs arising from discrepancies between the network under investigation and the pool of random graphs serving as a null model. Our aim was to provide a clear and accessible catalogue of such incongruities and their effect on the motif signature. As a case study, we explore the metabolic network of Escherichia coli and show that only by excluding ever more artefacts from the motif signature a strong and plausible correlation with the essentiality profile of metabolic reactions emerges. Artefacts in network motif analyses M. E. Beber et al. 3433 Artefacts in network motif analyses M. E. Beber et al. 3435
doi:10.1098/rsif.2012.0490 pmid:22896565 pmcid:PMC3481585 fatcat:47zooay6x5ditmdpicelghyrzy